List of publications

Department of Mesoscopic Physics
Department of Nonlinear Optics
Department of Physics of Nanostructures
Department of Theory of Condensed Matter

173 entries « ‹ 1 of 4 › »

2023
173.	Grzegorz Centała, Jarosław W. Kłos Shaping magnetization dynamics in a planar square dot by adjusting its surface anisotropy Journal of Magnetism and Magnetic Materials, 587 , pp. 171254, 2023, ISSN: 0304-8853. Abstract \| Links \| BibTeX @article{CENTALA2023171254, title = {Shaping magnetization dynamics in a planar square dot by adjusting its surface anisotropy}, author = {Grzegorz Centała and Jarosław W. Kłos}, url = {https://www.sciencedirect.com/science/article/pii/S0304885323009046}, doi = {https://doi.org/10.1016/j.jmmm.2023.171254}, issn = {0304-8853}, year = {2023}, date = {2023-09-22}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {587}, pages = {171254}, abstract = {A planar square dot is one of the simplest structures confined to three dimensions. Despite its geometrical simplicity, the description of the spin wave modes in this structure is not trivial due to the competition of dipolar and exchange interactions. An additional factor that makes this description challenging are the boundary conditions depend both on non-local dipolar interactions and local surface parameters such as surface anisotropy. In the presented work, we showed how the surface anisotropy applied at the lateral faces of the dot can tune the frequency of fundamental mode in the planar CoFeB dot, magnetized in an out-of-plane direction. Moreover, we analyzed the spin wave profile of the fundamental mode and the corresponding dynamic stray field. We showed that the asymmetric application of surface anisotropy produces an asymmetric profile of dynamic stray field for square dot and can be used to tailor inter-dot coupling. The calculations were performed with the use of the finite-element method.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A planar square dot is one of the simplest structures confined to three dimensions. Despite its geometrical simplicity, the description of the spin wave modes in this structure is not trivial due to the competition of dipolar and exchange interactions. An additional factor that makes this description challenging are the boundary conditions depend both on non-local dipolar interactions and local surface parameters such as surface anisotropy. In the presented work, we showed how the surface anisotropy applied at the lateral faces of the dot can tune the frequency of fundamental mode in the planar CoFeB dot, magnetized in an out-of-plane direction. Moreover, we analyzed the spin wave profile of the fundamental mode and the corresponding dynamic stray field. We showed that the asymmetric application of surface anisotropy produces an asymmetric profile of dynamic stray field for square dot and can be used to tailor inter-dot coupling. The calculations were performed with the use of the finite-element method. Close https://www.sciencedirect.com/science/article/pii/S0304885323009046 doi:https://doi.org/10.1016/j.jmmm.2023.171254 Close
172.	Jolanta Natalia Latosińska, Magdalena Latosińska, Janez Seliger, Veselko Žagar Exploring Partial Structural Disorder in Anhydrous Paraxanthine through Combined Experiment, Solid-State Computational Modelling, and Molecular Docking Processes, 11 (9), 2023, ISSN: 2227-9717. Abstract \| Links \| BibTeX @article{pr11092740, title = {Exploring Partial Structural Disorder in Anhydrous Paraxanthine through Combined Experiment, Solid-State Computational Modelling, and Molecular Docking}, author = {Jolanta Natalia Latosińska and Magdalena Latosińska and Janez Seliger and Veselko Žagar}, url = {https://www.mdpi.com/2227-9717/11/9/2740}, doi = {10.3390/pr11092740}, issn = {2227-9717}, year = {2023}, date = {2023-09-14}, journal = {Processes}, volume = {11}, number = {9}, abstract = {Paraxanthine (PX), a major metabolite of caffeine, a protective agent against Alzheimer’s and Parkinson’s disease, and a promising drug for the treatment of post-COVID 2019 anosmia and ageusia, has been studied in the solid state and protein–ligand complex. Partial disorder in PX, caused by the methyl group at the N(7) position, has been modelled and discussed. The relationship between the unusual structural disorder and the propensity to form a specific system of non-covalent bonds was analyzed. Three 1H-14N NMR-NQR (nuclear magnetic resonance–nuclear quadrupole resonance) experimental techniques were used, namely multiple frequency sweeps, Larmor frequency scanning, and the two-frequency irradiation, followed by solid-state computational modelling (density functional theory, supplemented by quantum theory of atoms in molecules, 3D Hirshfeld surfaces, and reduced density gradient), and molecular docking approaches. New quantitative methods for estimating changes in the global pattern of interactions under the influence of rotation of the methyl group in N(7) based on the Pompeiu–Hausdorff and Bhattacharayya metrics and the Wasserstein distance have been proposed and applied. A spectrum consisting of 12 lines, indicating the presence of 4 chemically inequivalent nitrogen sites in the PX molecule, was recorded, and the lines’ assignment to particular sites was made. The influence of the methyl rotation on the eigenvalues and eigenvectors of the electric field gradient tensor, NQR parameters, and resonance line positions was modelled in the solid (GGA/RPBE, m-GGA/RSCAN) and cluster (Minnesota M062X hybrid). Three factors have been found to determine structural disorder in PX: larger crystal voids near the methyl at N(7) than at N(1) (opening the path for the disorder), hyperconjugation strongly affecting the density distribution in the five-membered ring, and the involvement of the methyl group at N(7) in many non-covalent bonds that intercept (capture) subsequent jumping protons. The Pompeiu–Hausdorff and Bhattacharayya metrics and the Wasserstein distance confirmed the changes in the distribution and strength of non-covalent interactions throughout the molecule as a result of methyl rotation. This effect is clearly visible regardless of the type of metric, and its order of magnitude is consistent with the modulation effect of the NQR spectra (experimental and calculated). Through molecular docking, it was discovered that the PX moiety in protein–ligand complexes adopt the same methyl group conformation at N(7) as in the solid state. It was found that the cooperation–competition between the C-H⋯O hydrogen bonds and C-H⋯H-C dispersion interactions is the crucial factor that impedes methyl rotation and induces structural disorder, as well as being an important factor in the formation of the protein–ligand complexes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Paraxanthine (PX), a major metabolite of caffeine, a protective agent against Alzheimer’s and Parkinson’s disease, and a promising drug for the treatment of post-COVID 2019 anosmia and ageusia, has been studied in the solid state and protein–ligand complex. Partial disorder in PX, caused by the methyl group at the N(7) position, has been modelled and discussed. The relationship between the unusual structural disorder and the propensity to form a specific system of non-covalent bonds was analyzed. Three 1H-14N NMR-NQR (nuclear magnetic resonance–nuclear quadrupole resonance) experimental techniques were used, namely multiple frequency sweeps, Larmor frequency scanning, and the two-frequency irradiation, followed by solid-state computational modelling (density functional theory, supplemented by quantum theory of atoms in molecules, 3D Hirshfeld surfaces, and reduced density gradient), and molecular docking approaches. New quantitative methods for estimating changes in the global pattern of interactions under the influence of rotation of the methyl group in N(7) based on the Pompeiu–Hausdorff and Bhattacharayya metrics and the Wasserstein distance have been proposed and applied. A spectrum consisting of 12 lines, indicating the presence of 4 chemically inequivalent nitrogen sites in the PX molecule, was recorded, and the lines’ assignment to particular sites was made. The influence of the methyl rotation on the eigenvalues and eigenvectors of the electric field gradient tensor, NQR parameters, and resonance line positions was modelled in the solid (GGA/RPBE, m-GGA/RSCAN) and cluster (Minnesota M062X hybrid). Three factors have been found to determine structural disorder in PX: larger crystal voids near the methyl at N(7) than at N(1) (opening the path for the disorder), hyperconjugation strongly affecting the density distribution in the five-membered ring, and the involvement of the methyl group at N(7) in many non-covalent bonds that intercept (capture) subsequent jumping protons. The Pompeiu–Hausdorff and Bhattacharayya metrics and the Wasserstein distance confirmed the changes in the distribution and strength of non-covalent interactions throughout the molecule as a result of methyl rotation. This effect is clearly visible regardless of the type of metric, and its order of magnitude is consistent with the modulation effect of the NQR spectra (experimental and calculated). Through molecular docking, it was discovered that the PX moiety in protein–ligand complexes adopt the same methyl group conformation at N(7) as in the solid state. It was found that the cooperation–competition between the C-H⋯O hydrogen bonds and C-H⋯H-C dispersion interactions is the crucial factor that impedes methyl rotation and induces structural disorder, as well as being an important factor in the formation of the protein–ligand complexes. Close https://www.mdpi.com/2227-9717/11/9/2740 doi:10.3390/pr11092740 Close
171.	Sreedevi Janardhanan, Sławomir Mielcarek, Piotr Kuświk, Maciej Krawczyk, Aleksandra Trzaskowska High-resolution Brillouin light scattering study on Ti/Au/Co/Ni multilayer Journal of Magnetism and Magnetic Materials, 586 , pp. 171209, 2023, ISSN: 0304-8853. Abstract \| Links \| BibTeX @article{JANARDHANAN2023171209, title = {High-resolution Brillouin light scattering study on Ti/Au/Co/Ni multilayer}, author = {Sreedevi Janardhanan and Sławomir Mielcarek and Piotr Kuświk and Maciej Krawczyk and Aleksandra Trzaskowska}, url = {https://www.sciencedirect.com/science/article/pii/S0304885323008594}, doi = {https://doi.org/10.1016/j.jmmm.2023.171209}, issn = {0304-8853}, year = {2023}, date = {2023-09-01}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {586}, pages = {171209}, abstract = {The topic of this paper addresses the Brillouin light scattering (BLS) study of the spin-wave and surface acoustic wave dynamics in the multilayer consisting of Ti/Au/Co/Ni deposited on Si substrate. We make the quantitative analysis of spin-wave frequency under a range of wave vectors to determine the dispersion relation and to study the effect of the magnetic field. These findings were correlated with theoretical models to determine the magnetic system parameters, such as magnetization, Lande g factor, exchange stiffness constant etc. In addition to this, we have conducted finite element method based simulations to understand the nature of surface phonons and to determine the elastic tensor parameters for the Ti/Au/Co/Ni layer from the fitting of simulation results with the experiment data points.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The topic of this paper addresses the Brillouin light scattering (BLS) study of the spin-wave and surface acoustic wave dynamics in the multilayer consisting of Ti/Au/Co/Ni deposited on Si substrate. We make the quantitative analysis of spin-wave frequency under a range of wave vectors to determine the dispersion relation and to study the effect of the magnetic field. These findings were correlated with theoretical models to determine the magnetic system parameters, such as magnetization, Lande g factor, exchange stiffness constant etc. In addition to this, we have conducted finite element method based simulations to understand the nature of surface phonons and to determine the elastic tensor parameters for the Ti/Au/Co/Ni layer from the fitting of simulation results with the experiment data points. Close https://www.sciencedirect.com/science/article/pii/S0304885323008594 doi:https://doi.org/10.1016/j.jmmm.2023.171209 Close
170.	Mateusz Zelent, Mathieu Moalic, Michal Mruczkiewicz, Xiaoguang Li, Yan Zhou, Maciej Krawczyk Stabilization and racetrack application of asymmetric Néel skyrmions in hybrid nanostructures Scientific Reports, 13 (1), pp. 13572, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{zelent_stabilization_2023, title = {Stabilization and racetrack application of asymmetric Néel skyrmions in hybrid nanostructures}, author = {Mateusz Zelent and Mathieu Moalic and Michal Mruczkiewicz and Xiaoguang Li and Yan Zhou and Maciej Krawczyk}, url = {https://www.nature.com/articles/s41598-023-40236-z}, doi = {10.1038/s41598-023-40236-z}, issn = {2045-2322}, year = {2023}, date = {2023-08-21}, urldate = {2023-08-24}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {13572}, abstract = {Magnetic skyrmions, topological quasiparticles, are small stable magnetic textures that possess intriguing properties and potential for data storage applications. Hybrid nanostructures comprised of skyrmions and soft magnetic material can offer additional advantages for developing skyrmion-based spintronic and magnonic devices. We show that a Néel-type skyrmion confined within a nanodot placed on top of a ferromagnetic in-plane magnetized stripe produces a unique and compelling platform for exploring the mutual coupling between magnetization textures. The skyrmion induces an imprint upon the stripe, which, in turn, asymmetrically squeezes the skyrmion in the dot, increasing their size and the range of skyrmion stability at small values of Dzyaloshinskii–Moriya interaction, as well as introducing skyrmion bi-stability. Finally, by exploiting the properties of the skyrmion in a hybrid system, we demonstrate unlimited skyrmion transport along a racetrack, free of the skyrmion Hall effect.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnetic skyrmions, topological quasiparticles, are small stable magnetic textures that possess intriguing properties and potential for data storage applications. Hybrid nanostructures comprised of skyrmions and soft magnetic material can offer additional advantages for developing skyrmion-based spintronic and magnonic devices. We show that a Néel-type skyrmion confined within a nanodot placed on top of a ferromagnetic in-plane magnetized stripe produces a unique and compelling platform for exploring the mutual coupling between magnetization textures. The skyrmion induces an imprint upon the stripe, which, in turn, asymmetrically squeezes the skyrmion in the dot, increasing their size and the range of skyrmion stability at small values of Dzyaloshinskii–Moriya interaction, as well as introducing skyrmion bi-stability. Finally, by exploiting the properties of the skyrmion in a hybrid system, we demonstrate unlimited skyrmion transport along a racetrack, free of the skyrmion Hall effect. Close https://www.nature.com/articles/s41598-023-40236-z doi:10.1038/s41598-023-40236-z Close
169.	Victor A L'vov, Yulia Kharlan, Vladimir O Golub Nonrelaxational FMR peak broadening in spatially inhomogeneous films Journal of Magnetism and Magnetic Materials, 580 , pp. 170906, 2023, ISSN: 0304-8853. Abstract \| Links \| BibTeX @article{LVOV2023170906, title = {Nonrelaxational FMR peak broadening in spatially inhomogeneous films}, author = {Victor A L'vov and Yulia Kharlan and Vladimir O Golub}, url = {https://www.sciencedirect.com/science/article/pii/S0304885323005565}, doi = {https://doi.org/10.1016/j.jmmm.2023.170906}, issn = {0304-8853}, year = {2023}, date = {2023-08-15}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {580}, pages = {170906}, abstract = {The modification of magnetic properties in spatially inhomogeneous epitaxial films of magnetic shape memory alloys in martensitic state with the temperature variation has been studied. The proposed theoretical model is based on Landau theory of martensitic transformation and statistical model of martensitic state. It was shown that that spatial inhomogeneity of the material leads to the dispersion of local martensitic transformation temperatures resulting in the variation of local magnetic anisotropy values. This model allows describing the dramatic ferromagnetic resonance line broadening observed in the experiments in epitaxial films of magnetic shape memory alloys at low temperatures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The modification of magnetic properties in spatially inhomogeneous epitaxial films of magnetic shape memory alloys in martensitic state with the temperature variation has been studied. The proposed theoretical model is based on Landau theory of martensitic transformation and statistical model of martensitic state. It was shown that that spatial inhomogeneity of the material leads to the dispersion of local martensitic transformation temperatures resulting in the variation of local magnetic anisotropy values. This model allows describing the dramatic ferromagnetic resonance line broadening observed in the experiments in epitaxial films of magnetic shape memory alloys at low temperatures. Close https://www.sciencedirect.com/science/article/pii/S0304885323005565 doi:https://doi.org/10.1016/j.jmmm.2023.170906 Close
168.	Grzegorz Centała, Jarosław W. Kłos Compact localized states in magnonic Lieb lattices Scientific Reports, 13 (1), pp. 12676, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{centala_compact_2023, title = {Compact localized states in magnonic Lieb lattices}, author = {Grzegorz Centała and Jarosław W. Kłos}, url = {https://www.nature.com/articles/s41598-023-39816-w}, doi = {10.1038/s41598-023-39816-w}, issn = {2045-2322}, year = {2023}, date = {2023-08-04}, urldate = {2023-08-04}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {12676}, abstract = {Lieb lattice is one of the simplest bipartite lattices, where compact localized states (CLS) are observed. This type of localization is induced by the peculiar topology of the unit cell, where the modes are localized only on selected sublattices due to the destructive interference of partial waves. We demonstrate the possibility of magnonic Lieb lattice realization, where flat bands and CLS can be observed in the planar structure of sub-micron in-plane sizes. Using forward volume configuration, the Ga-doped YIG layer with cylindrical inclusions (without Ga content) arranged in a Lieb lattice with 250 nm period was investigated numerically (finite-element method). The structure was tailored to observe, for a lowest magnonic bands, the oscillatory and evanescent spin waves in inclusions and matrix, respectively. Such a design reproduces the Lieb lattice of nodes (inclusions) coupled to each other by the matrix with the CLS in flat bands.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Lieb lattice is one of the simplest bipartite lattices, where compact localized states (CLS) are observed. This type of localization is induced by the peculiar topology of the unit cell, where the modes are localized only on selected sublattices due to the destructive interference of partial waves. We demonstrate the possibility of magnonic Lieb lattice realization, where flat bands and CLS can be observed in the planar structure of sub-micron in-plane sizes. Using forward volume configuration, the Ga-doped YIG layer with cylindrical inclusions (without Ga content) arranged in a Lieb lattice with 250 nm period was investigated numerically (finite-element method). The structure was tailored to observe, for a lowest magnonic bands, the oscillatory and evanescent spin waves in inclusions and matrix, respectively. Such a design reproduces the Lieb lattice of nodes (inclusions) coupled to each other by the matrix with the CLS in flat bands. Close https://www.nature.com/articles/s41598-023-39816-w doi:10.1038/s41598-023-39816-w Close
167.	Krzysztof Sobucki, Wojciech Śmigaj, Piotr Graczyk, Maciej Krawczyk, Paweł Gruszecki Magnon-Optic Effects with Spin-Wave Leaky Modes: Tunable Goos-Hänchen Shift and Wood’s Anomaly Nano Letters, 23 (15), pp. 6979-6984, 2023, (PMID: 37523860). Abstract \| Links \| BibTeX @article{doi:10.1021/acs.nanolett.3c01592, title = {Magnon-Optic Effects with Spin-Wave Leaky Modes: Tunable Goos-Hänchen Shift and Wood’s Anomaly}, author = {Krzysztof Sobucki and Wojciech Śmigaj and Piotr Graczyk and Maciej Krawczyk and Paweł Gruszecki}, url = {https://doi.org/10.1021/acs.nanolett.3c01592}, doi = {10.1021/acs.nanolett.3c01592}, year = {2023}, date = {2023-07-31}, journal = {Nano Letters}, volume = {23}, number = {15}, pages = {6979-6984}, abstract = {We demonstrate numerically how a spin wave (SW) beam obliquely incident on the edge of a thin film placed below a ferromagnetic stripe can excite leaky SWs guided along the stripe. During propagation, leaky waves emit energy back into the layer in the form of plane waves and several laterally shifted parallel SW beams. This resonance excitation, combined with interference effects of the reflected and re-emitted waves, results in the magnonic Wood’s anomaly and a significant increase of the Goos-Hänchen shift magnitude. This yields a unique platform to control SW reflection and transdimensional magnonic router that can transfer SWs from a 2D platform into a 1D guided mode.}, note = {PMID: 37523860}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We demonstrate numerically how a spin wave (SW) beam obliquely incident on the edge of a thin film placed below a ferromagnetic stripe can excite leaky SWs guided along the stripe. During propagation, leaky waves emit energy back into the layer in the form of plane waves and several laterally shifted parallel SW beams. This resonance excitation, combined with interference effects of the reflected and re-emitted waves, results in the magnonic Wood’s anomaly and a significant increase of the Goos-Hänchen shift magnitude. This yields a unique platform to control SW reflection and transdimensional magnonic router that can transfer SWs from a 2D platform into a 1D guided mode. Close https://doi.org/10.1021/acs.nanolett.3c01592 doi:10.1021/acs.nanolett.3c01592 Close
166.	Uladzislau Makartsou, Mathieu Moalic, Mateusz Zelent, Michal Mruczkiewicz, Maciej Krawczyk Control of vortex chirality in a symmetric ferromagnetic ring using a ferromagnetic nanoelement Nanoscale, pp. -, 2023. Abstract \| Links \| BibTeX @article{D3NR00582H, title = {Control of vortex chirality in a symmetric ferromagnetic ring using a ferromagnetic nanoelement}, author = {Uladzislau Makartsou and Mathieu Moalic and Mateusz Zelent and Michal Mruczkiewicz and Maciej Krawczyk}, url = {http://dx.doi.org/10.1039/D3NR00582H}, doi = {10.1039/D3NR00582H}, year = {2023}, date = {2023-07-27}, journal = {Nanoscale}, pages = {-}, publisher = {The Royal Society of Chemistry}, abstract = {Controlling the vortex chirality in ferromagnetic nanodots and nanorings has been a topic of investigation for the last few years. Many control methods have been proposed and it has been found that the control is related to the breaking of the circular symmetry of the ring. In this paper, we present a theoretical study demonstrating the control of chirality in a symmetrical ferromagnetic nanoring by breaking the circular symmetry of the system by placing an elongated ferromagnetic nanoelement inside the ring. Here, the stray magnetostatic field exerted by the asymmetrically placed nanoelement determines the movement of the domain walls upon re-magnetization of the nanoring and the resulting chirality in remanence. Thus, the use of a nanoelement not only allows control of the chirality of the vortex state in an isolated ring, but also offers an opportunity to control magnetization in denser nanoring systems, as well as for spintronic and magnonic applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Controlling the vortex chirality in ferromagnetic nanodots and nanorings has been a topic of investigation for the last few years. Many control methods have been proposed and it has been found that the control is related to the breaking of the circular symmetry of the ring. In this paper, we present a theoretical study demonstrating the control of chirality in a symmetrical ferromagnetic nanoring by breaking the circular symmetry of the system by placing an elongated ferromagnetic nanoelement inside the ring. Here, the stray magnetostatic field exerted by the asymmetrically placed nanoelement determines the movement of the domain walls upon re-magnetization of the nanoring and the resulting chirality in remanence. Thus, the use of a nanoelement not only allows control of the chirality of the vortex state in an isolated ring, but also offers an opportunity to control magnetization in denser nanoring systems, as well as for spintronic and magnonic applications. Close http://dx.doi.org/10.1039/D3NR00582H doi:10.1039/D3NR00582H Close
165.	Wojciech Śmigaj, Krzysztof Sobucki, Paweł Gruszecki, Maciej Krawczyk Modal approach to modeling spin wave scattering Phys. Rev. B, 108 , pp. 014418, 2023. Abstract \| Links \| BibTeX @article{PhysRevB.108.014418, title = {Modal approach to modeling spin wave scattering}, author = {Wojciech Śmigaj and Krzysztof Sobucki and Paweł Gruszecki and Maciej Krawczyk}, url = {https://link.aps.org/doi/10.1103/PhysRevB.108.014418}, doi = {10.1103/PhysRevB.108.014418}, year = {2023}, date = {2023-07-01}, journal = {Phys. Rev. B}, volume = {108}, pages = {014418}, publisher = {American Physical Society}, abstract = {Efficient numerical methods are required for the design of optimized devices. In magnonics, the primary computational tool is micromagnetic simulations, which solve the Landau-Lifshitz equation discretized in time and space. However, their computational cost is high, and the complexity of their output hinders insight into the physics of the simulated system, especially in the case of multimode propagating-wave-based devices. We propose a finite-element modal method allowing an efficient solution of the scattering problem for dipole-exchange spin waves propagating perpendicularly to the magnetization direction. The method gives direct access to the scattering matrix of the whole system and its components. We extend the formula for the power carried by a magnetostatic mode in the Damon-Eshbach configuration to the case with exchange, allowing the scattering coefficients to be normalized to represent the fraction of the input power transferred to each output channel. We apply the method to the analysis of spin wave scattering on a basic functional block of magnonic circuits, consisting of a resonator dynamically coupled to a thin film. The results and the method are validated by comparison with micromagnetic simulations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Efficient numerical methods are required for the design of optimized devices. In magnonics, the primary computational tool is micromagnetic simulations, which solve the Landau-Lifshitz equation discretized in time and space. However, their computational cost is high, and the complexity of their output hinders insight into the physics of the simulated system, especially in the case of multimode propagating-wave-based devices. We propose a finite-element modal method allowing an efficient solution of the scattering problem for dipole-exchange spin waves propagating perpendicularly to the magnetization direction. The method gives direct access to the scattering matrix of the whole system and its components. We extend the formula for the power carried by a magnetostatic mode in the Damon-Eshbach configuration to the case with exchange, allowing the scattering coefficients to be normalized to represent the fraction of the input power transferred to each output channel. We apply the method to the analysis of spin wave scattering on a basic functional block of magnonic circuits, consisting of a resonator dynamically coupled to a thin film. The results and the method are validated by comparison with micromagnetic simulations. Close https://link.aps.org/doi/10.1103/PhysRevB.108.014418 doi:10.1103/PhysRevB.108.014418 Close
164.	Andrzej Grudka, Paweł Kurzyński, Tomasz P Polak, Adam S Sajna, Jan Wójcik, Antoni Wójcik Complementarity in quantum walks Journal of Physics A, 56 , pp. 275303, 2023. Abstract \| Links \| BibTeX @article{grudka23-2, title = {Complementarity in quantum walks}, author = {Andrzej Grudka and Paweł Kurzyński and Tomasz P Polak and Adam S Sajna and Jan Wójcik and Antoni Wójcik}, doi = {10.1088/1751-8121/acdcd0}, year = {2023}, date = {2023-06-19}, journal = {Journal of Physics A}, volume = {56}, pages = {275303}, abstract = {The eigenbases of two quantum observables, {\|ai⟩}Di=1 and {\|bj⟩}Dj=1, form mutually unbiased bases (MUB) if \|⟨ai \|bj⟩\| = 1/ √D for all i and j. In realistic situations MUB are hard to obtain and one looks for approximate MUB (AMUB), in which case the corresponding eigenbases obey \|⟨ai \|bj⟩\| ⩽ c/√D, where c is some positive constant independent of D. In majority of cases observables corresponding to MUB and AMUB do not have clear physical interpretation. Here we study discrete-time quantum walks (QWs) on d-cycles with a position and coin-dependent phase-shift. Such a model simulates a dynamics of a quantum particle moving on a ring with an artificial gauge field. In our case the amplitude of the phase-shift is governed by a single discrete parameter q. We solve the model analytically and observe that for prime d the eigenvectors of two QW evolution operators form AMUB. Namely, if d is prime the corresponding eigenvectors of the evolution operators, that act in the D-dimensional Hilbert space (D = 2d), obey \|⟨vq\|v ′q ′ ⟩\| ⩽√2/√D for q ̸= q ′ and for all \|vq⟩ and \|v ′q ′ ⟩. Finally, we show that the analogous AMUB relation still holds in the continuous version of this model, which corresponds to a one-dimensional Dirac particle.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The eigenbases of two quantum observables, {\|ai⟩}Di=1 and {\|bj⟩}Dj=1, form mutually unbiased bases (MUB) if \|⟨ai \|bj⟩\| = 1/ √D for all i and j. In realistic situations MUB are hard to obtain and one looks for approximate MUB (AMUB), in which case the corresponding eigenbases obey \|⟨ai \|bj⟩\| ⩽ c/√D, where c is some positive constant independent of D. In majority of cases observables corresponding to MUB and AMUB do not have clear physical interpretation. Here we study discrete-time quantum walks (QWs) on d-cycles with a position and coin-dependent phase-shift. Such a model simulates a dynamics of a quantum particle moving on a ring with an artificial gauge field. In our case the amplitude of the phase-shift is governed by a single discrete parameter q. We solve the model analytically and observe that for prime d the eigenvectors of two QW evolution operators form AMUB. Namely, if d is prime the corresponding eigenvectors of the evolution operators, that act in the D-dimensional Hilbert space (D = 2d), obey \|⟨vq\|v ′q ′ ⟩\| ⩽√2/√D for q ̸= q ′ and for all \|vq⟩ and \|v ′q ′ ⟩. Finally, we show that the analogous AMUB relation still holds in the continuous version of this model, which corresponds to a one-dimensional Dirac particle. Close doi:10.1088/1751-8121/acdcd0 Close
163.	Mateusz Gołębiewski, Hanna Reshetniak, Uladzislau Makartsou, Maciej Krawczyk, Arjen van den Berg, Sam Ladak, Anjan Barman Spin-Wave Spectral Analysis in Crescent-Shaped Ferromagnetic Nanorods Phys. Rev. Appl., 19 , pp. 064045, 2023. Abstract \| Links \| BibTeX @article{PhysRevApplied.19.064045, title = {Spin-Wave Spectral Analysis in Crescent-Shaped Ferromagnetic Nanorods}, author = {Mateusz Gołębiewski and Hanna Reshetniak and Uladzislau Makartsou and Maciej Krawczyk and Arjen van den Berg and Sam Ladak and Anjan Barman}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.19.064045}, doi = {10.1103/PhysRevApplied.19.064045}, year = {2023}, date = {2023-06-14}, journal = {Phys. Rev. Appl.}, volume = {19}, pages = {064045}, publisher = {American Physical Society}, abstract = {The research on the properties of spin waves (SWs) in three-dimensional nanosystems is an innovative idea in the field of magnonics. Mastering and understanding the nature of magnetization dynamics and binding of SWs at surfaces, edges, and in-volume parts of three-dimensional magnetic systems enables the discovery of alternative phenomena and suggests other possibilities for their use in magnonic and spintronic devices. In this work, we use numerical methods to study the effect of geometry and external magnetic field manipulations on the localization and dynamics of SWs in crescent-shaped (CS) waveguides. It is shown that changing the magnetic field direction in these waveguides breaks the symmetry and affects the localization of eigenmodes with respect to the static demagnetizing field. This, in turn, has a direct effect on their frequency. Furthermore, CS structures are found to be characterized by significant saturation at certain field orientations, resulting in a cylindrical magnetization distribution. Thus, we present chirality-based nonreciprocal dispersion relations for high-frequency SWs, which can be controlled by the field direction (shape symmetry) and its amplitude (saturation).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The research on the properties of spin waves (SWs) in three-dimensional nanosystems is an innovative idea in the field of magnonics. Mastering and understanding the nature of magnetization dynamics and binding of SWs at surfaces, edges, and in-volume parts of three-dimensional magnetic systems enables the discovery of alternative phenomena and suggests other possibilities for their use in magnonic and spintronic devices. In this work, we use numerical methods to study the effect of geometry and external magnetic field manipulations on the localization and dynamics of SWs in crescent-shaped (CS) waveguides. It is shown that changing the magnetic field direction in these waveguides breaks the symmetry and affects the localization of eigenmodes with respect to the static demagnetizing field. This, in turn, has a direct effect on their frequency. Furthermore, CS structures are found to be characterized by significant saturation at certain field orientations, resulting in a cylindrical magnetization distribution. Thus, we present chirality-based nonreciprocal dispersion relations for high-frequency SWs, which can be controlled by the field direction (shape symmetry) and its amplitude (saturation). Close https://link.aps.org/doi/10.1103/PhysRevApplied.19.064045 doi:10.1103/PhysRevApplied.19.064045 Close
162.	Bivas Rana, YoshiChika Otani Anisotropy of magnetic damping in Ta/CoFeB/MgO heterostructures Scientific Reports, 13 (1), pp. 8532, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{rana_anisotropy_2023, title = {Anisotropy of magnetic damping in Ta/CoFeB/MgO heterostructures}, author = {Bivas Rana and YoshiChika Otani}, url = {https://www.nature.com/articles/s41598-023-35739-8}, doi = {10.1038/s41598-023-35739-8}, issn = {2045-2322}, year = {2023}, date = {2023-05-26}, urldate = {2023-05-28}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {8532}, abstract = {Magnetic damping controls the performance and operational speed of many spintronics devices. Being a tensor quantity, the damping in magnetic thin films often shows anisotropic behavior with the magnetization orientation. Here, we have studied the anisotropy of damping in Ta/CoFeB/MgO heterostructures, deposited on thermally oxidized Si substrates, as a function of the orientation of magnetization. By performing ferromagnetic resonance (FMR) measurements based on spin pumping and inverse spin Hall effect (ISHE), we extract the damping parameter in those films and find that the anisotropy of damping contains four-fold and two-fold anisotropy terms. We infer that four-fold anisotropy originates from two-magnon scattering (TMS). By studying reference Ta/CoFeB/MgO films, deposited on LiNbO3 substrates, we find that the two-fold anisotropy is correlated with in-plane magnetic anisotropy (IMA) of the films, suggesting its origin as the anisotropy in bulk spin–orbit coupling (SOC) of CoFeB film. We conclude that when IMA is very small, it’s correlation with two-fold anisotropy cannot be experimentally identified. However, as IMA increases, it starts to show a correlation with two-fold anisotropy in damping. These results will be beneficial for designing future spintronics devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnetic damping controls the performance and operational speed of many spintronics devices. Being a tensor quantity, the damping in magnetic thin films often shows anisotropic behavior with the magnetization orientation. Here, we have studied the anisotropy of damping in Ta/CoFeB/MgO heterostructures, deposited on thermally oxidized Si substrates, as a function of the orientation of magnetization. By performing ferromagnetic resonance (FMR) measurements based on spin pumping and inverse spin Hall effect (ISHE), we extract the damping parameter in those films and find that the anisotropy of damping contains four-fold and two-fold anisotropy terms. We infer that four-fold anisotropy originates from two-magnon scattering (TMS). By studying reference Ta/CoFeB/MgO films, deposited on LiNbO3 substrates, we find that the two-fold anisotropy is correlated with in-plane magnetic anisotropy (IMA) of the films, suggesting its origin as the anisotropy in bulk spin–orbit coupling (SOC) of CoFeB film. We conclude that when IMA is very small, it’s correlation with two-fold anisotropy cannot be experimentally identified. However, as IMA increases, it starts to show a correlation with two-fold anisotropy in damping. These results will be beneficial for designing future spintronics devices. Close https://www.nature.com/articles/s41598-023-35739-8 doi:10.1038/s41598-023-35739-8 Close
161.	Dariia Popadiuk, Elena V. Tartakovskaya, Maciej Krawczyk, Kostyantyn Guslienko Emergent Magnetic Field and Nonzero Gyrovector of the Toroidal Magnetic Hopfion physica status solidi (RRL) – Rapid Research Letters, n/a (n/a), pp. 2300131, 2023. Abstract \| Links \| BibTeX @article{https://doi.org/10.1002/pssr.202300131, title = {Emergent Magnetic Field and Nonzero Gyrovector of the Toroidal Magnetic Hopfion}, author = {Dariia Popadiuk and Elena V. Tartakovskaya and Maciej Krawczyk and Kostyantyn Guslienko}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/pssr.202300131}, doi = {https://doi.org/10.1002/pssr.202300131}, year = {2023}, date = {2023-05-13}, journal = {physica status solidi (RRL) – Rapid Research Letters}, volume = {n/a}, number = {n/a}, pages = {2300131}, abstract = {Magnetic hopfions are localized magnetic solitons with a nonzero 3D topological charge (Hopf index). Herein, an analytical calculation of the magnetic hopfion gyrovector is presented and it is shown that it does not vanish even in an infinite sample. The calculation method is based on the concept of the emergent magnetic field. The particular case of the simplest nontrivial toroidal hopfion with the Hopf index \| QH \|=1$łeft\|right. Q_textĦ łeft\|right. = 1$ in the cylindrical magnetic dot is considered and dependencies of the gyrovector components on the dot sizes are calculated. Nonzero hopfion gyrovector is important in any description of the hopfion dynamics within the collective coordinate Thiele's approach.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnetic hopfions are localized magnetic solitons with a nonzero 3D topological charge (Hopf index). Herein, an analytical calculation of the magnetic hopfion gyrovector is presented and it is shown that it does not vanish even in an infinite sample. The calculation method is based on the concept of the emergent magnetic field. The particular case of the simplest nontrivial toroidal hopfion with the Hopf index \| QH \|=1$łeft\|right. Q_textĦ łeft\|right. = 1$ in the cylindrical magnetic dot is considered and dependencies of the gyrovector components on the dot sizes are calculated. Nonzero hopfion gyrovector is important in any description of the hopfion dynamics within the collective coordinate Thiele's approach. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/pssr.202300131 doi:https://doi.org/10.1002/pssr.202300131 Close
160.	R Mehta, Mathieu Moalic, Maciej Krawczyk, S Saha Tunability of spin-wave spectra in a 2D triangular shaped magnonic fractals Journal of Physics: Condensed Matter, 35 (32), pp. 324002, 2023. Abstract \| Links \| BibTeX @article{Mehta_2023, title = {Tunability of spin-wave spectra in a 2D triangular shaped magnonic fractals}, author = {R Mehta and Mathieu Moalic and Maciej Krawczyk and S Saha}, url = {https://dx.doi.org/10.1088/1361-648X/acd15f}, doi = {10.1088/1361-648X/acd15f}, year = {2023}, date = {2023-05-12}, journal = {Journal of Physics: Condensed Matter}, volume = {35}, number = {32}, pages = {324002}, publisher = {IOP Publishing}, abstract = {Reprogramming the structure of the magnonic bands during their operation is important for controlling spin waves in magnonic devices. Here, we report the tunability of the spin-wave spectra for a triangular shaped deterministic magnonic fractal, which is known as Sierpinski triangle by solving the Landau–Lifshitz–Gilbert equation using a micromagnetic simulations. The spin-wave dynamics change significantly with the variation of iteration number. A wide frequency gap is observed for a structure with an iteration number exceeding some value and a plenty of mini-frequency bandgaps at structures with high iteration number. The frequency gap could be controlled by varying the strength of the magnetic field. A sixfold symmetry in the frequency gap is observed with the variation of the azimuthal angle of the external magnetic field. The spatial distributions of the spin-wave modes allow to identify the bands surrounding the gap. The observations are important for the application of magnetic fractals as a reconfigurable aperiodic magnonic crystals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Reprogramming the structure of the magnonic bands during their operation is important for controlling spin waves in magnonic devices. Here, we report the tunability of the spin-wave spectra for a triangular shaped deterministic magnonic fractal, which is known as Sierpinski triangle by solving the Landau–Lifshitz–Gilbert equation using a micromagnetic simulations. The spin-wave dynamics change significantly with the variation of iteration number. A wide frequency gap is observed for a structure with an iteration number exceeding some value and a plenty of mini-frequency bandgaps at structures with high iteration number. The frequency gap could be controlled by varying the strength of the magnetic field. A sixfold symmetry in the frequency gap is observed with the variation of the azimuthal angle of the external magnetic field. The spatial distributions of the spin-wave modes allow to identify the bands surrounding the gap. The observations are important for the application of magnetic fractals as a reconfigurable aperiodic magnonic crystals. Close https://dx.doi.org/10.1088/1361-648X/acd15f Close
159.	J M Flores-Camacho, Bivas Rana, R E Balderas-Navarro, A Lastras-Martínez, Yoshichika Otani, Jorge Puebla Mid-infrared optical properties of non-magnetic-metal/CoFeB/MgO heterostructures Journal of Physics D: Applied Physics, 56 (31), pp. 315301, 2023. Abstract \| Links \| BibTeX @article{Flores-Camacho_2023, title = {Mid-infrared optical properties of non-magnetic-metal/CoFeB/MgO heterostructures}, author = {J M Flores-Camacho and Bivas Rana and R E Balderas-Navarro and A Lastras-Martínez and Yoshichika Otani and Jorge Puebla}, url = {https://dx.doi.org/10.1088/1361-6463/acd00f}, doi = {10.1088/1361-6463/acd00f}, year = {2023}, date = {2023-05-09}, journal = {Journal of Physics D: Applied Physics}, volume = {56}, number = {31}, pages = {315301}, publisher = {IOP Publishing}, abstract = {We report on the optical characterization of non-magnetic metal (NM)/ferromagnetic (Co20Fe60B20)/MgO heterostructures and interfaces by using mid infrared (MIR) spectroscopic ellipsometry at room temperature. We extracted for the MIR range the dielectric function (DF) of Co20Fe60B20, that is lacking in literature, from a multisample analysis. From the optical modeling of the heterostructures we detected and determined the dielectric tensor properties of a two-dimensional electron gas (2DEG) forming at the NM and the CoFeB interface. These properties comprise independent Drude parameters for the in-plane and out-of plane tensor components, with the latter having an epsilon-near-zero frequency within our working spectral range. A feature assigned to spin–orbit coupling (SOC) is identified. Furthermore, it is found that both, the interfacial properties, 2DEG Drude parameters and SOC strength, and the apparent DF of the MgO layer depend on the type of the underlying NM, namely, Pt, W, or Cu. The results reported here should be useful in tailoring novel phenomena in such types of heterostructures by assessing their optical response noninvasively, complementing existing characterization tools such as angle-resolved photoemission spectroscopy, and those related to electron/spin transport.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We report on the optical characterization of non-magnetic metal (NM)/ferromagnetic (Co20Fe60B20)/MgO heterostructures and interfaces by using mid infrared (MIR) spectroscopic ellipsometry at room temperature. We extracted for the MIR range the dielectric function (DF) of Co20Fe60B20, that is lacking in literature, from a multisample analysis. From the optical modeling of the heterostructures we detected and determined the dielectric tensor properties of a two-dimensional electron gas (2DEG) forming at the NM and the CoFeB interface. These properties comprise independent Drude parameters for the in-plane and out-of plane tensor components, with the latter having an epsilon-near-zero frequency within our working spectral range. A feature assigned to spin–orbit coupling (SOC) is identified. Furthermore, it is found that both, the interfacial properties, 2DEG Drude parameters and SOC strength, and the apparent DF of the MgO layer depend on the type of the underlying NM, namely, Pt, W, or Cu. The results reported here should be useful in tailoring novel phenomena in such types of heterostructures by assessing their optical response noninvasively, complementing existing characterization tools such as angle-resolved photoemission spectroscopy, and those related to electron/spin transport. Close https://dx.doi.org/10.1088/1361-6463/acd00f Close
158.	Andriy E. Serebryannikov, Diana C Skigin, Hodjat Hajian, Ekmel Ozbay Wide-angle and simultaneously wideband blazing (deflection) enabling multifunctionality in metagratings comprising epsilon-near-zero materials J. Opt. Soc. Am. B, 40 (5), pp. 1340–1349, 2023. Abstract \| Links \| BibTeX @article{Serebryannikov:23, title = {Wide-angle and simultaneously wideband blazing (deflection) enabling multifunctionality in metagratings comprising epsilon-near-zero materials}, author = {Andriy E. Serebryannikov and Diana C Skigin and Hodjat Hajian and Ekmel Ozbay}, url = {https://opg.optica.org/josab/abstract.cfm?URI=josab-40-5-1340}, doi = {10.1364/JOSAB.485457}, year = {2023}, date = {2023-05-01}, journal = {J. Opt. Soc. Am. B}, volume = {40}, number = {5}, pages = {1340--1349}, publisher = {Optica Publishing Group}, abstract = {This paper investigates diffractions by gratings made of a dispersive material in an epsilon-near-zero (ENZ) regime and having one-side corrugations, and those by two-component dielectric-ENZ gratings with the inner corrugations and flat outer interfaces. The goal is to achieve wideband and simultaneously wide-angle textminus1st order blazing (deflection) that may enable wideband spatial filtering and demultiplexing in reflection mode. Several typical scenarios are discussed, which differ in the maximum magnitude of the blazed wave and size of the blazing area observed on the frequency-incidence angle plane, as well as the contribution of the ranges of positive and negative permittivity in the vicinity of zero. The high capability of ENZ and dielectric-ENZ gratings in asymmetric reflection is demonstrated for three different levels of losses for the dispersive material.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close This paper investigates diffractions by gratings made of a dispersive material in an epsilon-near-zero (ENZ) regime and having one-side corrugations, and those by two-component dielectric-ENZ gratings with the inner corrugations and flat outer interfaces. The goal is to achieve wideband and simultaneously wide-angle textminus1st order blazing (deflection) that may enable wideband spatial filtering and demultiplexing in reflection mode. Several typical scenarios are discussed, which differ in the maximum magnitude of the blazed wave and size of the blazing area observed on the frequency-incidence angle plane, as well as the contribution of the ranges of positive and negative permittivity in the vicinity of zero. The high capability of ENZ and dielectric-ENZ gratings in asymmetric reflection is demonstrated for three different levels of losses for the dispersive material. Close https://opg.optica.org/josab/abstract.cfm?URI=josab-40-5-1340 doi:10.1364/JOSAB.485457 Close
157.	Arezoo Etesamirad, Yulia Kharlan, Rodolfo Rodriguez, Igor Barsukov, Roman Verba Controlling Selection Rules for Magnon Scattering in Nanomagnets by Spatial Symmetry Breaking Phys. Rev. Appl., 19 , pp. 044087, 2023. Abstract \| Links \| BibTeX @article{PhysRevApplied.19.044087, title = {Controlling Selection Rules for Magnon Scattering in Nanomagnets by Spatial Symmetry Breaking}, author = {Arezoo Etesamirad and Yulia Kharlan and Rodolfo Rodriguez and Igor Barsukov and Roman Verba}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.19.044087}, doi = {10.1103/PhysRevApplied.19.044087}, year = {2023}, date = {2023-04-27}, journal = {Phys. Rev. Appl.}, volume = {19}, pages = {044087}, publisher = {American Physical Society}, abstract = {Nanomagnets are the building blocks of many existing and emergent spintronic technologies. The magnetization dynamics of nanomagnets is often dominated by nonlinear processes, which have been recently shown to have many surprising features and far-reaching implications for applications. Here we develop a theoretical framework uncovering the selection rules for multimagnon processes and discuss their underlying mechanisms. For its technological relevance, we focus on the degenerate three-magnon process in thin elliptical nanodisks to illustrate our findings. We parameterize the selection rules through a set of magnon interaction coefficients which we calculate using micromagnetic simulations. We postulate the selection rules and investigate how they are altered by perturbations that break the symmetry of static magnetization configuration and spatial spin-wave profiles and that can be realized by applying off-symmetry-axis or nonuniform magnetic fields. Our work provides the phenomenological understanding of the mechanics of magnon interaction as well as the formalism for determining the interaction coefficients from simulations and experimental data. Our results serve as a guide to analyze the magnon processes inherently present in spin-torque devices in order to boost their performance or to engineer a specific nonlinear response in a nanomagnet used in a neuromorphic or quantum magnonic application.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Nanomagnets are the building blocks of many existing and emergent spintronic technologies. The magnetization dynamics of nanomagnets is often dominated by nonlinear processes, which have been recently shown to have many surprising features and far-reaching implications for applications. Here we develop a theoretical framework uncovering the selection rules for multimagnon processes and discuss their underlying mechanisms. For its technological relevance, we focus on the degenerate three-magnon process in thin elliptical nanodisks to illustrate our findings. We parameterize the selection rules through a set of magnon interaction coefficients which we calculate using micromagnetic simulations. We postulate the selection rules and investigate how they are altered by perturbations that break the symmetry of static magnetization configuration and spatial spin-wave profiles and that can be realized by applying off-symmetry-axis or nonuniform magnetic fields. Our work provides the phenomenological understanding of the mechanics of magnon interaction as well as the formalism for determining the interaction coefficients from simulations and experimental data. Our results serve as a guide to analyze the magnon processes inherently present in spin-torque devices in order to boost their performance or to engineer a specific nonlinear response in a nanomagnet used in a neuromorphic or quantum magnonic application. Close https://link.aps.org/doi/10.1103/PhysRevApplied.19.044087 doi:10.1103/PhysRevApplied.19.044087 Close
156.	Jan Kisielewski, Paweł Gruszecki, Maciej Krawczyk, Vitalii Zablotskii, Andrzej Maziewski Between waves and patterns: Spin wave freezing in films with Dzyaloshinskii-Moriya interaction Phys. Rev. B, 107 , pp. 134416, 2023. Abstract \| Links \| BibTeX @article{PhysRevB.107.134416, title = {Between waves and patterns: Spin wave freezing in films with Dzyaloshinskii-Moriya interaction}, author = {Jan Kisielewski and Paweł Gruszecki and Maciej Krawczyk and Vitalii Zablotskii and Andrzej Maziewski}, url = {https://link.aps.org/doi/10.1103/PhysRevB.107.134416}, doi = {10.1103/PhysRevB.107.134416}, year = {2023}, date = {2023-04-12}, journal = {Phys. Rev. B}, volume = {107}, pages = {134416}, publisher = {American Physical Society}, abstract = {The relationship between waves and static pattern formation is an intriguing effect and remains unexplained in many areas of physics, including magnetism. We study the spin-wave-mediated spin reorientation transition (SRT) in magnetic films with uniaxial magnetic anisotropy and Dzyaloshinskii-Moriya interaction (DMI). In particular, we show that propagating spin waves can freeze in the SRT, causing periodic magnetic domains to arise, which is reminiscent of the wave amplitude distribution. This process can take place under the influence of a change in the magnetic field, but also of other parameters. Interestingly, at the SRT, DMI nonreciprocity leads to the emergence of flowing magnetization patterns, which suggests a spontaneous breaking of translational symmetry, and the formation of magnonic space-time crystals. The described phenomena are general and should take place in a large family of magnetic materials. Therefore, the results should be of great importance for the further development of spintronics and magnonics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The relationship between waves and static pattern formation is an intriguing effect and remains unexplained in many areas of physics, including magnetism. We study the spin-wave-mediated spin reorientation transition (SRT) in magnetic films with uniaxial magnetic anisotropy and Dzyaloshinskii-Moriya interaction (DMI). In particular, we show that propagating spin waves can freeze in the SRT, causing periodic magnetic domains to arise, which is reminiscent of the wave amplitude distribution. This process can take place under the influence of a change in the magnetic field, but also of other parameters. Interestingly, at the SRT, DMI nonreciprocity leads to the emergence of flowing magnetization patterns, which suggests a spontaneous breaking of translational symmetry, and the formation of magnonic space-time crystals. The described phenomena are general and should take place in a large family of magnetic materials. Therefore, the results should be of great importance for the further development of spintronics and magnonics. Close https://link.aps.org/doi/10.1103/PhysRevB.107.134416 doi:10.1103/PhysRevB.107.134416 Close
155.	Grzegorz Chimczak, Anna Kowalewska‑Kudłaszyk, Ewelina Lange, Karol Bartkiewicz, Jan Peřina Jr. The effect of thermal photons on exceptional points in coupled resonators. Scientific Reports, 13 , pp. 5859, 2023. Abstract \| Links \| BibTeX @article{Chimczak2023, title = {The effect of thermal photons on exceptional points in coupled resonators.}, author = {Grzegorz Chimczak and Anna Kowalewska‑Kudłaszyk and Ewelina Lange and Karol Bartkiewicz and Jan Peřina Jr.}, url = {https://www.nature.com/articles/s41598-023-32864-2}, doi = {https://doi.org/10.1038/s41598-023-32864-2}, year = {2023}, date = {2023-04-11}, journal = {Scientific Reports}, volume = {13}, pages = {5859}, abstract = {We analyse two quantum systems with hidden parity-time ( PT ) symmetry: one is an optical device, whereas another is a superconducting microwave-frequency device. To investigate their symmetry, we introduce a damping frame (DF), in which loss and gain terms for a given Hamiltonian are balanced. We show that the non-Hermitian Hamiltonians of both systems can be tuned to reach an exceptional point (EP), i.e., the point in parameter space at which a transition from broken to unbroken hidden PT symmetry takes place. We calculate a degeneracy of a Liouvillian superoperator, which is called the Liouvillian exceptional point (LEP), and show that, in the optical domain, LEP is equivalent to EP obtained from the non-Hermitian Hamiltonian (HEP). We also report breaking the equivalence between LEP and HEP by a non-zero number of thermal photons for the microwave-frequency system.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We analyse two quantum systems with hidden parity-time ( PT ) symmetry: one is an optical device, whereas another is a superconducting microwave-frequency device. To investigate their symmetry, we introduce a damping frame (DF), in which loss and gain terms for a given Hamiltonian are balanced. We show that the non-Hermitian Hamiltonians of both systems can be tuned to reach an exceptional point (EP), i.e., the point in parameter space at which a transition from broken to unbroken hidden PT symmetry takes place. We calculate a degeneracy of a Liouvillian superoperator, which is called the Liouvillian exceptional point (LEP), and show that, in the optical domain, LEP is equivalent to EP obtained from the non-Hermitian Hamiltonian (HEP). We also report breaking the equivalence between LEP and HEP by a non-zero number of thermal photons for the microwave-frequency system. Close https://www.nature.com/articles/s41598-023-32864-2 doi:https://doi.org/10.1038/s41598-023-32864-2 Close
154.	Jolanta Natalia Latosińska, Magdalena Latosińska, Janez Seliger, Veselko Žagar, Tomaž Apih, Paweł Grieb Elucidating the Role of Noncovalent Interactions in Favipiravir, a Drug Active against Various Human RNA Viruses; a 1H-14N NQDR/Periodic DFT/QTAIM/RDS/3D Hirshfeld Surfaces Combined Study Molecules, 28 (8), 2023, ISSN: 1420-3049. Abstract \| Links \| BibTeX @article{molecules28083308, title = {Elucidating the Role of Noncovalent Interactions in Favipiravir, a Drug Active against Various Human RNA Viruses; a 1H-14N NQDR/Periodic DFT/QTAIM/RDS/3D Hirshfeld Surfaces Combined Study}, author = {Jolanta Natalia Latosińska and Magdalena Latosińska and Janez Seliger and Veselko Žagar and Tomaž Apih and Paweł Grieb}, url = {https://www.mdpi.com/1420-3049/28/8/3308}, doi = {10.3390/molecules28083308}, issn = {1420-3049}, year = {2023}, date = {2023-04-07}, journal = {Molecules}, volume = {28}, number = {8}, abstract = {Favipiravir (6-fluoro-3-hydroxypyrazine-2-carboxamide, FPV), an active pharmaceutical component of the drug discovered and registered in March 2014 in Japan under the name Avigan, with an indication for pandemic influenza, has been studied. The study of this compound was prompted by the idea that effective processes of recognition and binding of FPV to the nucleic acid are affected predominantly by the propensity to form intra- and intermolecular interactions. Three nuclear quadrupole resonance experimental techniques, namely 1H-14N cross-relaxation, multiple frequency sweeps, and two-frequency irradiation, followed by solid-state computational modelling (density functional theory supplemented by the quantum theory of atoms in molecules, 3D Hirshfeld Surfaces, and reduced density gradient) approaches were applied. The complete NQR spectrum consisting of nine lines indicating the presence of three chemically inequivalent nitrogen sites in the FPV molecule was detected, and the assignment of lines to particular sites was performed. The description of the nearest vicinity of all three nitrogen atoms was used to characterize the nature of the intermolecular interactions from the perspective of the local single atoms and to draw some conclusions on the nature of the interactions required for effective recognition and binding. The propensity to form the electrostatic N−H···O, N−H···N, and C−H···O intermolecular hydrogen bonds competitive with two intramolecular hydrogen bonds, strong O−H···O and very weak N−H···N, closing the 5-member ring and stiffening the structure, as well as π···π and F···F dispersive interactions, were analysed in detail. The hypothesis regarding the similarity of the interaction pattern in the solid and the RNA template was verified. It was discovered that the -NH2 group in the crystal participates in intermolecular hydrogen bonds N–H···N and N–H···O, in the precatalytic state only in N–H···O, while in the active state in N–H···N and N–H···O hydrogen bonds, which is of importance to link FVP to the RNA template. Our study elucidates the binding modes of FVP (in crystal, precatalytic, and active forms) in detail and should guide the design of more potent analogues targeting SARS-CoV-2. Strong direct binding of FVP-RTP to both the active site and cofactor discovered by us suggests a possible alternative, allosteric mechanism of FVP action, which may explain the scattering of the results of clinical trials or the synergistic effect observed in combined treatment against SARS-CoV-2.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Favipiravir (6-fluoro-3-hydroxypyrazine-2-carboxamide, FPV), an active pharmaceutical component of the drug discovered and registered in March 2014 in Japan under the name Avigan, with an indication for pandemic influenza, has been studied. The study of this compound was prompted by the idea that effective processes of recognition and binding of FPV to the nucleic acid are affected predominantly by the propensity to form intra- and intermolecular interactions. Three nuclear quadrupole resonance experimental techniques, namely 1H-14N cross-relaxation, multiple frequency sweeps, and two-frequency irradiation, followed by solid-state computational modelling (density functional theory supplemented by the quantum theory of atoms in molecules, 3D Hirshfeld Surfaces, and reduced density gradient) approaches were applied. The complete NQR spectrum consisting of nine lines indicating the presence of three chemically inequivalent nitrogen sites in the FPV molecule was detected, and the assignment of lines to particular sites was performed. The description of the nearest vicinity of all three nitrogen atoms was used to characterize the nature of the intermolecular interactions from the perspective of the local single atoms and to draw some conclusions on the nature of the interactions required for effective recognition and binding. The propensity to form the electrostatic N−H···O, N−H···N, and C−H···O intermolecular hydrogen bonds competitive with two intramolecular hydrogen bonds, strong O−H···O and very weak N−H···N, closing the 5-member ring and stiffening the structure, as well as π···π and F···F dispersive interactions, were analysed in detail. The hypothesis regarding the similarity of the interaction pattern in the solid and the RNA template was verified. It was discovered that the -NH2 group in the crystal participates in intermolecular hydrogen bonds N–H···N and N–H···O, in the precatalytic state only in N–H···O, while in the active state in N–H···N and N–H···O hydrogen bonds, which is of importance to link FVP to the RNA template. Our study elucidates the binding modes of FVP (in crystal, precatalytic, and active forms) in detail and should guide the design of more potent analogues targeting SARS-CoV-2. Strong direct binding of FVP-RTP to both the active site and cofactor discovered by us suggests a possible alternative, allosteric mechanism of FVP action, which may explain the scattering of the results of clinical trials or the synergistic effect observed in combined treatment against SARS-CoV-2. Close https://www.mdpi.com/1420-3049/28/8/3308 doi:10.3390/molecules28083308 Close
153.	Angshuman Deka, Bivas Rana, YoshiChika Otani, Yasuhiro Fukuma Ferromagnetic resonance excited by interfacial microwave electric field: the role of current-induced torques Journal of Physics: Condensed Matter, 35 (21), pp. 214003, 2023. Abstract \| Links \| BibTeX @article{Deka_2023, title = {Ferromagnetic resonance excited by interfacial microwave electric field: the role of current-induced torques}, author = {Angshuman Deka and Bivas Rana and YoshiChika Otani and Yasuhiro Fukuma}, url = {https://dx.doi.org/10.1088/1361-648X/acc377}, doi = {10.1088/1361-648X/acc377}, year = {2023}, date = {2023-03-24}, journal = {Journal of Physics: Condensed Matter}, volume = {35}, number = {21}, pages = {214003}, publisher = {IOP Publishing}, abstract = {Excitation of magnetization dynamics in magnetic materials, especially in ultrathin ferromagnetic films, is of utmost importance for developing various ultrafast spintronics devices. Recently, the excitation of magnetization dynamics, i.e. ferromagnetic resonance (FMR) via electric field-induced modulation of interfacial magnetic anisotropies, has received particular attention due to several advantages, including lower power consumption. However, several additional torques generated by unavoidable microwave current induced because of the capacitive nature of the junctions may also contribute to the excitation of FMR apart from electric field-induced torques. Here, we study the FMR signals excited by applying microwave signal across the metal-oxide junction in CoFeB/MgO heterostructures with Pt and Ta buffer layers. Analysis of the resonance line shape and angular dependent behavior of resonance amplitude revealed that apart from voltage-controlled in-plane magnetic anisotropy (VC-IMA) torque a significant contribution can also arises from spin-torques and Oersted field torques originating from the flow of microwave current through metal-oxide junction. Surprisingly, the overall contribution from spin-torques and Oersted field torques are comparable to the VC-IMA torque contribution, even for a device with negligible defects. This study will be beneficial for designing future electric field-controlled spintronics devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Excitation of magnetization dynamics in magnetic materials, especially in ultrathin ferromagnetic films, is of utmost importance for developing various ultrafast spintronics devices. Recently, the excitation of magnetization dynamics, i.e. ferromagnetic resonance (FMR) via electric field-induced modulation of interfacial magnetic anisotropies, has received particular attention due to several advantages, including lower power consumption. However, several additional torques generated by unavoidable microwave current induced because of the capacitive nature of the junctions may also contribute to the excitation of FMR apart from electric field-induced torques. Here, we study the FMR signals excited by applying microwave signal across the metal-oxide junction in CoFeB/MgO heterostructures with Pt and Ta buffer layers. Analysis of the resonance line shape and angular dependent behavior of resonance amplitude revealed that apart from voltage-controlled in-plane magnetic anisotropy (VC-IMA) torque a significant contribution can also arises from spin-torques and Oersted field torques originating from the flow of microwave current through metal-oxide junction. Surprisingly, the overall contribution from spin-torques and Oersted field torques are comparable to the VC-IMA torque contribution, even for a device with negligible defects. This study will be beneficial for designing future electric field-controlled spintronics devices. Close https://dx.doi.org/10.1088/1361-648X/acc377 Close
152.	Oleksandr Pastukh, Malgorzata Kac, Svitlana Pastukh, Dominika Kuźma, Mateusz Zelent, Maciej Krawczyk, Łukasz Laskowski Magnetic Behavior of the Arrays of Iron Cylindrical Nanostructures: Atomistic Spin Model Simulations Crystals, 13 (3), 2023, ISSN: 2073-4352. Abstract \| Links \| BibTeX @article{cryst13030537, title = {Magnetic Behavior of the Arrays of Iron Cylindrical Nanostructures: Atomistic Spin Model Simulations}, author = {Oleksandr Pastukh and Malgorzata Kac and Svitlana Pastukh and Dominika Kuźma and Mateusz Zelent and Maciej Krawczyk and Łukasz Laskowski}, url = {https://www.mdpi.com/2073-4352/13/3/537}, doi = {10.3390/cryst13030537}, issn = {2073-4352}, year = {2023}, date = {2023-03-21}, journal = {Crystals}, volume = {13}, number = {3}, abstract = {Cylindrical ferromagnetic nanowires are of particular interest in nanomaterials science due to various manufacturing methods and a wide range of applications in nanotechnology, with special attention given to those with diameters less than the single domain limit. In the current study, the simulations of magnetic properties of isolated iron nanowires with a diameter of 5 nm and various aspect ratios, as well as two types of arrays of such nanowires (with hexagonal and square arrangement), were performed using atomistic spin model. In the case of a single nanowire, change of coercive field for different applied field directions with aspect ratio was discussed. It was shown that the evolution of the magnetization reversal mechanism from coherent rotation to domain wall propagation appears with increasing length of single nanowire. For the arrays of cylindrical nanostructures, it was revealed that different number of nearest neighbors for each nanostructure in square and hexagonal arrays have an influence on their magnetostatic interactions, which are the most significant for shortest interwire distances. The corresponding spin configurations during the remagnetization process showed the appearance of intermediate magnetization states (when a part of wires is magnetized parallel and part antiparallel to the field direction), connected with Barkhausen effect, which influence the observed hysteresis curves.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Cylindrical ferromagnetic nanowires are of particular interest in nanomaterials science due to various manufacturing methods and a wide range of applications in nanotechnology, with special attention given to those with diameters less than the single domain limit. In the current study, the simulations of magnetic properties of isolated iron nanowires with a diameter of 5 nm and various aspect ratios, as well as two types of arrays of such nanowires (with hexagonal and square arrangement), were performed using atomistic spin model. In the case of a single nanowire, change of coercive field for different applied field directions with aspect ratio was discussed. It was shown that the evolution of the magnetization reversal mechanism from coherent rotation to domain wall propagation appears with increasing length of single nanowire. For the arrays of cylindrical nanostructures, it was revealed that different number of nearest neighbors for each nanostructure in square and hexagonal arrays have an influence on their magnetostatic interactions, which are the most significant for shortest interwire distances. The corresponding spin configurations during the remagnetization process showed the appearance of intermediate magnetization states (when a part of wires is magnetized parallel and part antiparallel to the field direction), connected with Barkhausen effect, which influence the observed hysteresis curves. Close https://www.mdpi.com/2073-4352/13/3/537 doi:10.3390/cryst13030537 Close
151.	Andrzej Grudka, Marcin Karczewski, Paweł Kurzyński, Jan Wójcik, Antoni Wójcik Topological invariants in quantum walks Physical Review A, 107 , pp. 032201, 2023. Abstract \| Links \| BibTeX @article{grudka23, title = {Topological invariants in quantum walks}, author = {Andrzej Grudka and Marcin Karczewski and Paweł Kurzyński and Jan Wójcik and Antoni Wójcik}, doi = {10.1103/PhysRevA.107.032201}, year = {2023}, date = {2023-03-01}, journal = {Physical Review A}, volume = {107}, pages = {032201}, abstract = {Discrete-time quantum walks (DTQWs) provide a convenient platform for a realization of many topological phases in noninteracting systems. They often offer more possibilities than systems with a static Hamiltonian. Nevertheless, researchers are still looking for DTQW symmetries protecting topological phases and for definitions of appropriate topological invariants. Although the majority of DTQW studies on this topic focus on the so-called split-step quantum walk, two distinct topological phases can be observed in more basic models. Here we infer topological properties of the basic DTQWs directly from the mapping of the Brillouin zone to the Bloch Hamiltonian. We show that for translation-symmetric systems they can be characterized by a homotopy relative to special points. We also propose a topological invariant corresponding to this concept. This invariant indicates the number of edge states at the interface between two distinct phases.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Discrete-time quantum walks (DTQWs) provide a convenient platform for a realization of many topological phases in noninteracting systems. They often offer more possibilities than systems with a static Hamiltonian. Nevertheless, researchers are still looking for DTQW symmetries protecting topological phases and for definitions of appropriate topological invariants. Although the majority of DTQW studies on this topic focus on the so-called split-step quantum walk, two distinct topological phases can be observed in more basic models. Here we infer topological properties of the basic DTQWs directly from the mapping of the Brillouin zone to the Bloch Hamiltonian. We show that for translation-symmetric systems they can be characterized by a homotopy relative to special points. We also propose a topological invariant corresponding to this concept. This invariant indicates the number of edge states at the interface between two distinct phases. Close doi:10.1103/PhysRevA.107.032201 Close
150.	Flavio Capotondi, Alexander Lichtenstein, Serguei Molodtsov, Leonard Mueller, Andre Philippi-Kobs, Przemysław Piekarz, Konrad J. Kapcia, Victor Tkachenko, Beata Ziaja Electronic processes occurring during ultrafast demagnetization of cobalt triggered by x-ray photons tuned to the Co $L_3$ resonance Phys. Rev. B, 107 , pp. 094402, 2023. Links \| BibTeX @article{PhysRevB.107.094402, title = {Electronic processes occurring during ultrafast demagnetization of cobalt triggered by x-ray photons tuned to the Co $L_3$ resonance}, author = {Flavio Capotondi and Alexander Lichtenstein and Serguei Molodtsov and Leonard Mueller and Andre Philippi-Kobs and Przemysław Piekarz and Konrad J. Kapcia and Victor Tkachenko and Beata Ziaja}, url = {https://link.aps.org/doi/10.1103/PhysRevB.107.094402}, doi = {10.1103/PhysRevB.107.094402}, year = {2023}, date = {2023-03-01}, journal = {Phys. Rev. B}, volume = {107}, pages = {094402}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://link.aps.org/doi/10.1103/PhysRevB.107.094402 doi:10.1103/PhysRevB.107.094402 Close
149.	Kacper Wrześniewski Dynamics of Superconducting Correlations Induced by Hopping in Serial Double Quantum Dot System Acta Physica Polonica A, 143 (2), pp. 160, 2023. Abstract \| Links \| BibTeX @article{Wrześniewski2023, title = {Dynamics of Superconducting Correlations Induced by Hopping in Serial Double Quantum Dot System}, author = {Kacper Wrześniewski}, url = {http://przyrbwn.icm.edu.pl/APP/apphome.html}, doi = {10.12693/APhysPolA.143.160}, year = {2023}, date = {2023-02-27}, journal = {Acta Physica Polonica A}, volume = {143}, number = {2}, pages = {160}, abstract = {We study the quench dynamics of superconducting pairing correlations in the double quantum dotsystem coupled to superconducting and normal metallic electrodes. The quantum dots are initiallyisolated from each other, and the subsequent dynamics are induced by the sudden switching on hoppingbetween them. We focus on the time-dependence of the real and imaginary parts of dots pairing potentialand the role of the hopping amplitude and on-site Coulomb correlations. For relatively small hoppingvalues, the evolution of the pairing potential is suppressed due to a strong single-occupation blockade.As the hopping amplitude increases, the pairing potential is dynamically redistributed between thedots and can eventually assume values of opposite signs. This effect is enhanced by the presence ofstrong on-site Coulomb interactions. The discussed numerical results are obtained by means of thetime-dependent numerical renormalization group approach.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We study the quench dynamics of superconducting pairing correlations in the double quantum dotsystem coupled to superconducting and normal metallic electrodes. The quantum dots are initiallyisolated from each other, and the subsequent dynamics are induced by the sudden switching on hoppingbetween them. We focus on the time-dependence of the real and imaginary parts of dots pairing potentialand the role of the hopping amplitude and on-site Coulomb correlations. For relatively small hoppingvalues, the evolution of the pairing potential is suppressed due to a strong single-occupation blockade.As the hopping amplitude increases, the pairing potential is dynamically redistributed between thedots and can eventually assume values of opposite signs. This effect is enhanced by the presence ofstrong on-site Coulomb interactions. The discussed numerical results are obtained by means of thetime-dependent numerical renormalization group approach. Close http://przyrbwn.icm.edu.pl/APP/apphome.html doi:10.12693/APhysPolA.143.160 Close
148.	Krzysztof Paweł Wójcik, Piotr Majek Majorana Coupling and Kondo Screening of Localized Spins Acta Physica Polonica A, 143 (2), pp. 207, 2023. Abstract \| Links \| BibTeX @article{Wójcik2023, title = {Majorana Coupling and Kondo Screening of Localized Spins}, author = {Krzysztof Paweł Wójcik and Piotr Majek}, url = {http://przyrbwn.icm.edu.pl/APP/PDF/143/app143z2p15.pdf}, doi = {10.12693/APhysPolA.143.207}, year = {2023}, date = {2023-02-27}, journal = {Acta Physica Polonica A}, volume = {143}, number = {2}, pages = {207}, abstract = {We perform a theoretical analysis of the fate of the local magnetic moment of a quantum dot coupled to a normal metallic lead and a topological superconducting wire hosting Majorana modes at the ends. By means of simple analytical tools and numerical renormalization group calculations, we show that the proximity of the Majorana mode reduces the magnetic moment from 1/4, characteristic of a free spin 1/2, to 1/16. Coupling to the normal lead then causes the Kondo effect, such that the magnetic moment is fully screened below the Kondo temperature. The latter is vastly increased for strong coupling to Majorana mode.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We perform a theoretical analysis of the fate of the local magnetic moment of a quantum dot coupled to a normal metallic lead and a topological superconducting wire hosting Majorana modes at the ends. By means of simple analytical tools and numerical renormalization group calculations, we show that the proximity of the Majorana mode reduces the magnetic moment from 1/4, characteristic of a free spin 1/2, to 1/16. Coupling to the normal lead then causes the Kondo effect, such that the magnetic moment is fully screened below the Kondo temperature. The latter is vastly increased for strong coupling to Majorana mode. Close http://przyrbwn.icm.edu.pl/APP/PDF/143/app143z2p15.pdf doi:10.12693/APhysPolA.143.207 Close
147.	J Feilhauer, Mateusz Zelent, Zhiwang Zhang, J Christensen, M Mruczkiewicz Unidirectional spin-wave edge modes in magnonic crystal APL Materials, 11 (2), pp. 021104, 2023. Abstract \| Links \| BibTeX @article{doi:10.1063/5.0134099, title = {Unidirectional spin-wave edge modes in magnonic crystal}, author = {J Feilhauer and Mateusz Zelent and Zhiwang Zhang and J Christensen and M Mruczkiewicz}, url = {https://doi.org/10.1063/5.0134099}, doi = {10.1063/5.0134099}, year = {2023}, date = {2023-02-13}, journal = {APL Materials}, volume = {11}, number = {2}, pages = {021104}, abstract = {We present a numerical demonstration of magnonic crystals hosting unidirectional, topologically protected edge states. The magnonic crystal is formed of dipolarly coupled Permalloy triangles. We show that due to the geometry of the block, the size of the structure can be scaled up. In addition, edge states can be found over a wide frequency range. Experimental detection of edge excitations in the considered system can be done with state-of-the-art techniques. Thus, we demonstrate a proof-of-concept magnonic Chern topological insulator nanostructure with simple geometry feasible for experimental realization. Furthermore, by tuning the strength of the perpendicular magnetic field, we induce a topological phase transition, which results in the change of direction of the topological edge state. Then, we demonstrate the magnonic switch based on this effect.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We present a numerical demonstration of magnonic crystals hosting unidirectional, topologically protected edge states. The magnonic crystal is formed of dipolarly coupled Permalloy triangles. We show that due to the geometry of the block, the size of the structure can be scaled up. In addition, edge states can be found over a wide frequency range. Experimental detection of edge excitations in the considered system can be done with state-of-the-art techniques. Thus, we demonstrate a proof-of-concept magnonic Chern topological insulator nanostructure with simple geometry feasible for experimental realization. Furthermore, by tuning the strength of the perpendicular magnetic field, we induce a topological phase transition, which results in the change of direction of the topological edge state. Then, we demonstrate the magnonic switch based on this effect. Close https://doi.org/10.1063/5.0134099 doi:10.1063/5.0134099 Close
146.	Kuan-Yi Lee, Jhen-Dong Lin, Adam Miranowicz, Franco Nori, Huan-Yu Ku, Yueh-Nan Chen Steering-enhanced quantum metrology using superpositions of noisy phase shifts Phys. Rev. Res., 5 , pp. 013103, 2023. Abstract \| Links \| BibTeX @article{23prr-lee, title = {Steering-enhanced quantum metrology using superpositions of noisy phase shifts}, author = {Kuan-Yi Lee and Jhen-Dong Lin and Adam Miranowicz and Franco Nori and Huan-Yu Ku and Yueh-Nan Chen}, url = {https://link.aps.org/doi/10.1103/PhysRevResearch.5.013103}, doi = {10.1103/PhysRevResearch.5.013103}, year = {2023}, date = {2023-02-13}, journal = {Phys. Rev. Res.}, volume = {5}, pages = {013103}, publisher = {American Physical Society}, abstract = {Quantum steering is an important correlation in quantum information theory. A recent work [Nat. Commun. 12, 2410 (2021)] showed that quantum steering is also useful for quantum metrology. Here, we extend the exploration of steering-enhanced quantum metrology from single noiseless phase shifts to superpositions of noisy phase shifts. As concrete examples, we consider a control system that manipulates a target system to pass through a superposition of either dephased or depolarized phase shifts channels. We show that using such superpositions of noisy phase shifts can suppress the effects of noise and improve metrology. Furthermore, we also implemented proof-of-principle experiments for a superposition of dephased phase shifts on the IBM quantum experience, demonstrating a clear improvement on metrology.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Quantum steering is an important correlation in quantum information theory. A recent work [Nat. Commun. 12, 2410 (2021)] showed that quantum steering is also useful for quantum metrology. Here, we extend the exploration of steering-enhanced quantum metrology from single noiseless phase shifts to superpositions of noisy phase shifts. As concrete examples, we consider a control system that manipulates a target system to pass through a superposition of either dephased or depolarized phase shifts channels. We show that using such superpositions of noisy phase shifts can suppress the effects of noise and improve metrology. Furthermore, we also implemented proof-of-principle experiments for a superposition of dephased phase shifts on the IBM quantum experience, demonstrating a clear improvement on metrology. Close https://link.aps.org/doi/10.1103/PhysRevResearch.5.013103 doi:10.1103/PhysRevResearch.5.013103 Close
145.	Liubov Ivzhenko, Aleksey Girich, Artem Hrinchenko, Oleh Yermakov Mechanically Tunable Topological Transition and High-Directional Propagation of Surface Waves at Bilayer Hyperbolic Metasurfaces 2022 IEEE 2nd Ukrainian Microwave Week (UkrMW), pp. 214-217, 2023. Abstract \| Links \| BibTeX @inproceedings{10037146, title = {Mechanically Tunable Topological Transition and High-Directional Propagation of Surface Waves at Bilayer Hyperbolic Metasurfaces}, author = {Liubov Ivzhenko and Aleksey Girich and Artem Hrinchenko and Oleh Yermakov}, doi = {10.1109/UkrMW58013.2022.10037146}, year = {2023}, date = {2023-02-13}, booktitle = {2022 IEEE 2nd Ukrainian Microwave Week (UkrMW)}, pages = {214-217}, abstract = {We propose simple and efficient way to control the propagation regime and direction of spoof surface plasmon-polaritons localized at bilayer hyperbolic metasurfaces. We demonstrate the photonic topological transition at the same frequency implemented with a mutual rotation of the metasurface layers. Finally, we show the tunable multidirectional in-plane canalization of surface waves adjusting by the interlayer coupling. These results discover new opportunities for the manipulation over surface waves at metasurfaces.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Close We propose simple and efficient way to control the propagation regime and direction of spoof surface plasmon-polaritons localized at bilayer hyperbolic metasurfaces. We demonstrate the photonic topological transition at the same frequency implemented with a mutual rotation of the metasurface layers. Finally, we show the tunable multidirectional in-plane canalization of surface waves adjusting by the interlayer coupling. These results discover new opportunities for the manipulation over surface waves at metasurfaces. Close doi:10.1109/UkrMW58013.2022.10037146 Close
144.	Sergey Polevoy, Ganna Kharchenko, Tetiana Kalmykova, Yevhenii Ostryzhnyi, Liubov Ivzhenko, Oleh Yermakov Polarization-Controlled Excitation of Surface Waves at Self-Complementary Metasurface 2022 IEEE 2nd Ukrainian Microwave Week (UkrMW), pp. 222-225, 2023. Abstract \| Links \| BibTeX @inproceedings{10036966, title = {Polarization-Controlled Excitation of Surface Waves at Self-Complementary Metasurface}, author = {Sergey Polevoy and Ganna Kharchenko and Tetiana Kalmykova and Yevhenii Ostryzhnyi and Liubov Ivzhenko and Oleh Yermakov}, doi = {10.1109/UkrMW58013.2022.10036966}, year = {2023}, date = {2023-02-13}, booktitle = {2022 IEEE 2nd Ukrainian Microwave Week (UkrMW)}, pages = {222-225}, abstract = {In this work, we study the surface electromagnetic waves propagating along the self-complementary metasurface. We propose a way to excite the surface waves of the necessary polarization by using the TE-TM degeneracy property of the self-complementary metasurface. In particular, we demonstrate the excitation of surface waves with linear horizontal, vertical and diagonal as well as circular polarizations. The proposed technique opens new possibilities for the in-plane signal transferring and transformation.}, keywords = {}, pubstate = {published}, tppubtype = {inproceedings} } Close In this work, we study the surface electromagnetic waves propagating along the self-complementary metasurface. We propose a way to excite the surface waves of the necessary polarization by using the TE-TM degeneracy property of the self-complementary metasurface. In particular, we demonstrate the excitation of surface waves with linear horizontal, vertical and diagonal as well as circular polarizations. The proposed technique opens new possibilities for the in-plane signal transferring and transformation. Close doi:10.1109/UkrMW58013.2022.10036966 Close
143.	Anand Manaparambil, Ireneusz Weymann Nonequilibrium Seebeck effect and thermoelectric efficiency of Kondo-correlated molecular junctions Phys. Rev. B, 107 , pp. 085404, 2023. Abstract \| Links \| BibTeX @article{Manaparambil2023, title = {Nonequilibrium Seebeck effect and thermoelectric efficiency of Kondo-correlated molecular junctions}, author = {Anand Manaparambil and Ireneusz Weymann}, url = {https://journals.aps.org/prb/abstract/10.1103/PhysRevB.107.085404}, doi = {10.1103/PhysRevB.107.085404}, year = {2023}, date = {2023-02-07}, journal = {Phys. Rev. B}, volume = {107}, pages = {085404}, abstract = {We theoretically study the nonequilibrium thermoelectric transport properties of a strongly-correlated molecule (or quantum dot) embedded in a tunnel junction. Assuming that the coupling of the molecule to the contacts is asymmetric, we determine the nonlinear current driven by the voltage and temperature gradients by using the perturbation theory. However, the subsystem consisting of the molecule strongly coupled to one of the contacts is solved by using the numerical renormalization group method, which allows for accurate description of Kondo correlations. We study the temperature gradient and voltage dependence of the nonlinear and differential Seebeck coefficients for various initial configurations of the system. In particular, we show that in the Coulomb blockade regime with singly occupied molecule, both thermopowers exhibit sign changes due to the Kondo correlations at nonequilibrium conditions. Moreover, we determine the nonlinear heat current and thermoelectric efficiency, demonstrating that the system can work as a heat engine with considerable efficiency, depending on the transport regime.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We theoretically study the nonequilibrium thermoelectric transport properties of a strongly-correlated molecule (or quantum dot) embedded in a tunnel junction. Assuming that the coupling of the molecule to the contacts is asymmetric, we determine the nonlinear current driven by the voltage and temperature gradients by using the perturbation theory. However, the subsystem consisting of the molecule strongly coupled to one of the contacts is solved by using the numerical renormalization group method, which allows for accurate description of Kondo correlations. We study the temperature gradient and voltage dependence of the nonlinear and differential Seebeck coefficients for various initial configurations of the system. In particular, we show that in the Coulomb blockade regime with singly occupied molecule, both thermopowers exhibit sign changes due to the Kondo correlations at nonequilibrium conditions. Moreover, we determine the nonlinear heat current and thermoelectric efficiency, demonstrating that the system can work as a heat engine with considerable efficiency, depending on the transport regime. Close https://journals.aps.org/prb/abstract/10.1103/PhysRevB.107.085404 doi:10.1103/PhysRevB.107.085404 Close
142.	Marceli Koralewski, Małgorzata Paprzycka Faraday effect and refractive index of some imidazolium-based room-temperature ionic liquids and magnetic ionic liquids Journal of Molecular Liquids, 375 , pp. 121375, 2023. Abstract \| Links \| BibTeX @article{Koralewski2023, title = {Faraday effect and refractive index of some imidazolium-based room-temperature ionic liquids and magnetic ionic liquids}, author = {Marceli Koralewski and Małgorzata Paprzycka}, doi = {10.1016/j.molliq.2023.121375}, year = {2023}, date = {2023-02-02}, journal = {Journal of Molecular Liquids}, volume = {375}, pages = {121375}, abstract = {Knowledge of the Faraday effect (FE) is very important in fundamental research and applications. Here, we report FE and refractive index studies for two magnetic ionic liquids (MILs), namely 1-ethyl- and 1-butyl-3-methylimidazolium tetrachloroferrate. Similar studies are also conducted for ionic liquids (ILs) that have a diamagnetic counteranion in place of [FeCl4]. The magnitudes of the Verdet constants of MILs are comparable and exhibit a negative sign. Furthermore, they are about one order larger than those of ILs with a diamagnetic counteranion of a positive sign. The Verdet constant shows monotonic variations as a function of wavelength in the range from 450 to 650 nm and is mainly related to charge transfer transitions in [FeCl4], with bands located in the UV region, though the contribution of d-d transitions in Fe+3 is negligible. A model for describing the measured Verdet constant data as a function of wavelength and temperature is given with respective values of effective Faraday A-, B-, and D-terms. The introduction of an empirical rule allows the estimation of Verdet constants of iron and imidazolium derivative based MILs, which are in some cases very high, thus indicating their potential in photonics applications. Imidazole shows a positive and nearly-two orders lower magnitude of the Verdet constant. The mixture of an MIL and acetonitrile allows the tuning of both the Verdet constant and the refractive index. The refractive indices, thermo-optic coefficients, and electronic polarizabilities of MILs are higher than those of ILs with a diamagnetic counteranion.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Knowledge of the Faraday effect (FE) is very important in fundamental research and applications. Here, we report FE and refractive index studies for two magnetic ionic liquids (MILs), namely 1-ethyl- and 1-butyl-3-methylimidazolium tetrachloroferrate. Similar studies are also conducted for ionic liquids (ILs) that have a diamagnetic counteranion in place of [FeCl4]. The magnitudes of the Verdet constants of MILs are comparable and exhibit a negative sign. Furthermore, they are about one order larger than those of ILs with a diamagnetic counteranion of a positive sign. The Verdet constant shows monotonic variations as a function of wavelength in the range from 450 to 650 nm and is mainly related to charge transfer transitions in [FeCl4], with bands located in the UV region, though the contribution of d-d transitions in Fe+3 is negligible. A model for describing the measured Verdet constant data as a function of wavelength and temperature is given with respective values of effective Faraday A-, B-, and D-terms. The introduction of an empirical rule allows the estimation of Verdet constants of iron and imidazolium derivative based MILs, which are in some cases very high, thus indicating their potential in photonics applications. Imidazole shows a positive and nearly-two orders lower magnitude of the Verdet constant. The mixture of an MIL and acetonitrile allows the tuning of both the Verdet constant and the refractive index. The refractive indices, thermo-optic coefficients, and electronic polarizabilities of MILs are higher than those of ILs with a diamagnetic counteranion. Close doi:10.1016/j.molliq.2023.121375 Close
141.	Jolanta Natalia Latosińska, Magdalena Latosińska, Andrzei Orzeszko, Jan Krzysztof Maurin Synthesis and Crystal Structure of Adamantylated 4,5,6,7-tetrahalogeno-1H-benzimidazoles Novel Multi-Target Ligands (Potential CK2, M2 and SARS-CoV-2 Inhibitors). X-ray/DFT/QTAIM/Hirshfeld Surfaces/Molecular Docking Study Molecules, 28 (1), pp. 147, 2023. Abstract \| Links \| BibTeX @article{Latosińska2023, title = {Synthesis and Crystal Structure of Adamantylated 4,5,6,7-tetrahalogeno-1H-benzimidazoles Novel Multi-Target Ligands (Potential CK2, M2 and SARS-CoV-2 Inhibitors). X-ray/DFT/QTAIM/Hirshfeld Surfaces/Molecular Docking Study }, author = {Jolanta Natalia Latosińska and Magdalena Latosińska and Andrzei Orzeszko and Jan Krzysztof Maurin }, doi = {10.3390/molecules28010147}, year = {2023}, date = {2023-01-02}, journal = {Molecules}, volume = {28}, number = {1}, pages = {147}, abstract = {A series of new congeners, 1-[2-(1-adamantyl)ethyl]-1H-benzimidazole (AB) and 1-[2-(1-adamantyl)ethyl]-4,5,6,7-tetrahalogeno-1H-benzimidazole (Hal=Cl, Br, I; tClAB, tBrAB, tIAB), have been synthesized and studied. These novel multi-target ligands combine a benzimidazole ring known to show antitumor activity and an adamantyl moiety showing anti-influenza activity. Their crystal structures were determined by X-ray, while intermolecular interactions were studied using topological Bader’s Quantum Theory of Atoms in Molecules, Hirshfeld Surfaces, CLP and PIXEL approaches. The newly synthesized compounds crystallize within two different space groups, P-1 (AB and tIAB) and P21/c (tClAB and tBrAB). A number of intramolecular hydrogen bonds, C−H⋯Hal (Hal=Cl, Br, I), were found in all halogen-containing congeners studied, but the intermolecular C−H⋯N hydrogen bond was detected only in AB and tIAB, while C−Hal⋯π only in tClAB and tBrAB. The interplay between C−H⋯N and C−H⋯Hal hydrogen bonds and a shift from the strong (C−H⋯Cl) to the very weak (C−H⋯I) attractive interactions upon Hal exchange, supplemented with Hal⋯Hal overlapping, determines the differences in the symmetry of crystalline packing and is crucial from the biological point of view. The hypothesis about the potential dual inhibitor role of the newly synthesized congeners was verified using molecular docking and the congeners were found to be pharmaceutically attractive as Human Casein Kinase 2, CK2, inhibitors, Membrane Matrix 2 Protein, M2, blockers and Severe Acute Respiratory Syndrome Coronavirus 2, SARS-CoV-2, inhibitors. The addition of adamantyl moiety seems to broaden and modify the therapeutic indices of the 4,5,6,7-tetrahalogeno-1H-benzimidazoles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A series of new congeners, 1-[2-(1-adamantyl)ethyl]-1H-benzimidazole (AB) and 1-[2-(1-adamantyl)ethyl]-4,5,6,7-tetrahalogeno-1H-benzimidazole (Hal=Cl, Br, I; tClAB, tBrAB, tIAB), have been synthesized and studied. These novel multi-target ligands combine a benzimidazole ring known to show antitumor activity and an adamantyl moiety showing anti-influenza activity. Their crystal structures were determined by X-ray, while intermolecular interactions were studied using topological Bader’s Quantum Theory of Atoms in Molecules, Hirshfeld Surfaces, CLP and PIXEL approaches. The newly synthesized compounds crystallize within two different space groups, P-1 (AB and tIAB) and P21/c (tClAB and tBrAB). A number of intramolecular hydrogen bonds, C−H⋯Hal (Hal=Cl, Br, I), were found in all halogen-containing congeners studied, but the intermolecular C−H⋯N hydrogen bond was detected only in AB and tIAB, while C−Hal⋯π only in tClAB and tBrAB. The interplay between C−H⋯N and C−H⋯Hal hydrogen bonds and a shift from the strong (C−H⋯Cl) to the very weak (C−H⋯I) attractive interactions upon Hal exchange, supplemented with Hal⋯Hal overlapping, determines the differences in the symmetry of crystalline packing and is crucial from the biological point of view. The hypothesis about the potential dual inhibitor role of the newly synthesized congeners was verified using molecular docking and the congeners were found to be pharmaceutically attractive as Human Casein Kinase 2, CK2, inhibitors, Membrane Matrix 2 Protein, M2, blockers and Severe Acute Respiratory Syndrome Coronavirus 2, SARS-CoV-2, inhibitors. The addition of adamantyl moiety seems to broaden and modify the therapeutic indices of the 4,5,6,7-tetrahalogeno-1H-benzimidazoles. Close doi:10.3390/molecules28010147 Close
140.	Paweł Gruszecki, Jan Kisielewski Influence of Dzyaloshinskii–Moriya interaction and perpendicular anisotropy on spin waves propagation in stripe domain patterns and spin spirals Scientific Reports, 13 (1), pp. 1218, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{gruszecki_influence_2023, title = {Influence of Dzyaloshinskii–Moriya interaction and perpendicular anisotropy on spin waves propagation in stripe domain patterns and spin spirals}, author = {Paweł Gruszecki and Jan Kisielewski}, url = {https://www.nature.com/articles/s41598-023-28271-2}, doi = {10.1038/s41598-023-28271-2}, issn = {2045-2322}, year = {2023}, date = {2023-01-01}, urldate = {2023-01-25}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {1218}, abstract = {Texture-based magnonics focuses on the utilization of spin waves in magnetization textures to process information. Using micromagnetic simulations, we study how (1) the dynamic magnetic susceptibility, (2) dispersion relations, and (3) the equilibrium magnetic configurations in periodic magnetization textures in a ultrathin ferromagnetic film in remanence depend on the values of the Dzyaloshinskii–Moriya interaction and the perpendicular magnetocrystalline anisotropy. We observe that for large Dzyaloshinskii–Moriya interaction values, spin spirals with periods of tens of nanometers are the preferred state; for small Dzyaloshinskii–Moriya interaction values and large anisotropies, stripe domain patterns with over a thousand times larger period are preferable. We observe and explain the selectivity of the excitation of resonant modes by a linearly polarized microwave field. We study the propagation of spin waves along and perpendicular to the direction of the periodicity. For propagation along the direction of the periodicity, we observe a bandgap that closes and reopens, which is accompanied by a swap in the order of the bands. For waves propagating in the perpendicular direction, some modes can be used for unidirectional channeling of spin waves. Overall, our findings are promising in sensing and signal processing applications and explain the fundamental properties of periodic magnetization textures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Texture-based magnonics focuses on the utilization of spin waves in magnetization textures to process information. Using micromagnetic simulations, we study how (1) the dynamic magnetic susceptibility, (2) dispersion relations, and (3) the equilibrium magnetic configurations in periodic magnetization textures in a ultrathin ferromagnetic film in remanence depend on the values of the Dzyaloshinskii–Moriya interaction and the perpendicular magnetocrystalline anisotropy. We observe that for large Dzyaloshinskii–Moriya interaction values, spin spirals with periods of tens of nanometers are the preferred state; for small Dzyaloshinskii–Moriya interaction values and large anisotropies, stripe domain patterns with over a thousand times larger period are preferable. We observe and explain the selectivity of the excitation of resonant modes by a linearly polarized microwave field. We study the propagation of spin waves along and perpendicular to the direction of the periodicity. For propagation along the direction of the periodicity, we observe a bandgap that closes and reopens, which is accompanied by a swap in the order of the bands. For waves propagating in the perpendicular direction, some modes can be used for unidirectional channeling of spin waves. Overall, our findings are promising in sensing and signal processing applications and explain the fundamental properties of periodic magnetization textures. Close https://www.nature.com/articles/s41598-023-28271-2 doi:10.1038/s41598-023-28271-2 Close
139.	Shashank Shekhar, Sławomir Mielcarek, Y Otani, Bivas Rana, Aleksandra Trzaskowska Influence of CoFeB layer thickness on elastic parameters in CoFeB/MgO heterostructures Scientific Reports, 13 (1), pp. 10668, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{shekhar_influence_2023, title = {Influence of CoFeB layer thickness on elastic parameters in CoFeB/MgO heterostructures}, author = {Shashank Shekhar and Sławomir Mielcarek and Y Otani and Bivas Rana and Aleksandra Trzaskowska}, url = {https://www.nature.com/articles/s41598-023-37808-4}, doi = {10.1038/s41598-023-37808-4}, issn = {2045-2322}, year = {2023}, date = {2023-01-01}, urldate = {2023-07-04}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {10668}, abstract = {The surface acoustic waves, i.e., surface phonons may have huge potential for future spintronic devices, if coupled to other waves (e.g., spin waves) or quasiparticles. In order to understand the coupling of acoustic phonons with the spin degree of freedom, especially in magnetic thin film-based heterostructures, one needs to investigate the properties of phonons in those heterostructures. This also allows us to determine the elastic properties of individual magnetic layers and the effective elastic parameters of the whole stacks. Here, we study frequency versus wavevector dispersion of thermally excited SAWs in CoFeB/MgO heterostructures with varying CoFeB thickness by employing Brillouin light spectroscopy. The experimental results are corroborated by finite element method-based simulations. From the best agreement of simulation results with the experiments, we find out the elastic tensor parameters for CoFeB layer. Additionally, we estimate the effective elastic parameters (elastic tensors, Young’s modulus, Poisson’s ratio) of the whole stacks for varying CoFeB thickness. Interestingly, the simulation results, either considering elastic parameters of individual layers or considering effective elastic parameters of whole stacks, show good agreement with the experimental results. These extracted elastic parameters will be very useful to understand the interaction of phonons with other quasiparticles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The surface acoustic waves, i.e., surface phonons may have huge potential for future spintronic devices, if coupled to other waves (e.g., spin waves) or quasiparticles. In order to understand the coupling of acoustic phonons with the spin degree of freedom, especially in magnetic thin film-based heterostructures, one needs to investigate the properties of phonons in those heterostructures. This also allows us to determine the elastic properties of individual magnetic layers and the effective elastic parameters of the whole stacks. Here, we study frequency versus wavevector dispersion of thermally excited SAWs in CoFeB/MgO heterostructures with varying CoFeB thickness by employing Brillouin light spectroscopy. The experimental results are corroborated by finite element method-based simulations. From the best agreement of simulation results with the experiments, we find out the elastic tensor parameters for CoFeB layer. Additionally, we estimate the effective elastic parameters (elastic tensors, Young’s modulus, Poisson’s ratio) of the whole stacks for varying CoFeB thickness. Interestingly, the simulation results, either considering elastic parameters of individual layers or considering effective elastic parameters of whole stacks, show good agreement with the experimental results. These extracted elastic parameters will be very useful to understand the interaction of phonons with other quasiparticles. Close https://www.nature.com/articles/s41598-023-37808-4 doi:10.1038/s41598-023-37808-4 Close
138.	Jan Barański, Magaldena Barańska, Tomasz Zienkiewicz, Konrad J. Kapcia Quench dynamics of Fano-like resonances in the presence of the on-dot superconducting pairing Scientific Reports, 13 (1), pp. 7639, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{Baranski2023, title = {Quench dynamics of Fano-like resonances in the presence of the on-dot superconducting pairing}, author = {Jan Bara{ń}ski and Magaldena Bara{ń}ska and Tomasz Zienkiewicz and Konrad J. Kapcia}, url = {https://doi.org/10.1038/s41598-023-34376-5}, doi = {10.1038/s41598-023-34376-5}, issn = {2045-2322}, year = {2023}, date = {2023-01-01}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {7639}, abstract = {We explore the electron dynamics of a system composed of double quantum dot embedded between metallic and superconducting leads in a “T-shape” geometry. In nanoscopic systems, where electron transfer between electrodes can be realized via different paths, interference effects play an important role. For double quantum dot system in the chosen geometry, interference of electrons transferred between electrodes via the interfacial quantum dot and electrons scattered on the side dot gives rise to Fano-like interference. If such a system is additionally coupled to a superconducting electrode, together with the well-understood Fano resonance an additional resonance appears on the opposite side of the Fermi level. In the recent work (Barański et al. in Sci Rep 10:2881, 2020), we showed that this resonance occurs solely as a result of the local pairing of non-scattered electrons with scattered ones. In this work, considering the quench dynamics, we explore how much time is required for formation of each of these resonances. In particular, (i) we analyze the charge oscillations between subsystems; (ii) we estimate the time required for each resonance to achieve stable equilibrium upon an abrupt change of interdot connection; (iii) we discuss a typical energy and time scales for experiments on similar architectures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We explore the electron dynamics of a system composed of double quantum dot embedded between metallic and superconducting leads in a “T-shape” geometry. In nanoscopic systems, where electron transfer between electrodes can be realized via different paths, interference effects play an important role. For double quantum dot system in the chosen geometry, interference of electrons transferred between electrodes via the interfacial quantum dot and electrons scattered on the side dot gives rise to Fano-like interference. If such a system is additionally coupled to a superconducting electrode, together with the well-understood Fano resonance an additional resonance appears on the opposite side of the Fermi level. In the recent work (Barański et al. in Sci Rep 10:2881, 2020), we showed that this resonance occurs solely as a result of the local pairing of non-scattered electrons with scattered ones. In this work, considering the quench dynamics, we explore how much time is required for formation of each of these resonances. In particular, (i) we analyze the charge oscillations between subsystems; (ii) we estimate the time required for each resonance to achieve stable equilibrium upon an abrupt change of interdot connection; (iii) we discuss a typical energy and time scales for experiments on similar architectures. Close https://doi.org/10.1038/s41598-023-34376-5 doi:10.1038/s41598-023-34376-5 Close
137.	Jakub Skórka, Konrad J. Kapcia, Paweł T. Jochym, Andrzej Ptok Chiral phonons in binary compounds ABi (A = K, Rb, Cs) with P21/c structure Materials Today Communications, 35 , pp. 105888, 2023, ISSN: 2352-4928. Abstract \| Links \| BibTeX @article{SKORKA2023105888, title = {Chiral phonons in binary compounds ABi (A = K, Rb, Cs) with P21/c structure}, author = {Jakub Skórka and Konrad J. Kapcia and Paweł T. Jochym and Andrzej Ptok}, url = {https://www.sciencedirect.com/science/article/pii/S2352492823005792}, doi = {https://doi.org/10.1016/j.mtcomm.2023.105888}, issn = {2352-4928}, year = {2023}, date = {2023-01-01}, journal = {Materials Today Communications}, volume = {35}, pages = {105888}, abstract = {Binary compounds ABi (A = K, Rb, Cs) crystallize in P21/c structure containing both clockwise and anticlockwise chiral chains of Bi atoms. Electronic band structure exhibits the insulating nature of these systems, with the band gap about 0.25eV. The presented study of dynamical properties confirm a stability of the system with P21/c symmetry. The crystal structure contains the quasi-one-dimensional Bi chains, exhibiting four-fold-like rotational “local” symmetry. Nevertheless, the system formally possesses two-fold rotational symmetry. Independently of the absence of the three-fold (or higher) rotational symmetry axes for the whole crystal, the chiral modes propagate along the Bi atom chains in these systems. We discuss basic properties of these modes in monoatomic chiral chains. We show that the two-fold rotational symmetry axis affects the main properties of the chiral phonons, which are not realized at the high-symmetry points, but along some paths between them in the reciprocal space. In addition, in the doped system, the chiral phonons possess non-zero total angular momentum.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Binary compounds ABi (A = K, Rb, Cs) crystallize in P21/c structure containing both clockwise and anticlockwise chiral chains of Bi atoms. Electronic band structure exhibits the insulating nature of these systems, with the band gap about 0.25eV. The presented study of dynamical properties confirm a stability of the system with P21/c symmetry. The crystal structure contains the quasi-one-dimensional Bi chains, exhibiting four-fold-like rotational “local” symmetry. Nevertheless, the system formally possesses two-fold rotational symmetry. Independently of the absence of the three-fold (or higher) rotational symmetry axes for the whole crystal, the chiral modes propagate along the Bi atom chains in these systems. We discuss basic properties of these modes in monoatomic chiral chains. We show that the two-fold rotational symmetry axis affects the main properties of the chiral phonons, which are not realized at the high-symmetry points, but along some paths between them in the reciprocal space. In addition, in the doped system, the chiral phonons possess non-zero total angular momentum. Close https://www.sciencedirect.com/science/article/pii/S2352492823005792 doi:https://doi.org/10.1016/j.mtcomm.2023.105888 Close
136.	Jan Barański, Konrad J. Kapcia Dynamics of Fano-Like Resonances in Double-Quantum-Dot Systems Acta Physica Polonica A, 143 (2), pp. 143, 2023. Abstract \| Links \| BibTeX @article{Jan_Baranski2023-id, title = {Dynamics of Fano-Like Resonances in Double-Quantum-Dot Systems}, author = {Jan Barański and Konrad J. Kapcia}, url = {http://appol.ifpan.edu.pl/index.php/appa/article/view/143_143}, year = {2023}, date = {2023-01-01}, journal = {Acta Physica Polonica A}, volume = {143}, number = {2}, pages = {143}, abstract = {Quantum interference effects appearing in mesoscopic heterostructures have been extensively studied in static conditions over the last decades. It is interesting to examine the dynamics of these phenomena and get insight into the process of the formation of interference patterns. In this work, we analyze the time required for the formation of Fano-like resonances in a double quantum dot system. We examined the time evolution of conductance upon establishing an abrupt connection between quantum dots. Asymmetric Fano lines are characterized by the close coexistence of resonant enhancement and resonant suppression. Therefore, we pay particular attention to voltages, which in the static case, correspond to both these features. Our research shows that the analyzed resonances are characterized by two time scales: (i) the first one related to charge oscillations between subsystems and mostly governed by the interdot coupling constant and the relative position of energy levels of quantum dots, and (ii) the second one associated to the electron scattering on a continuum of states and responsible for the relaxation. We also show that the time required for achieving a static solution is different for voltages corresponding to local minima and local maxima.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Quantum interference effects appearing in mesoscopic heterostructures have been extensively studied in static conditions over the last decades. It is interesting to examine the dynamics of these phenomena and get insight into the process of the formation of interference patterns. In this work, we analyze the time required for the formation of Fano-like resonances in a double quantum dot system. We examined the time evolution of conductance upon establishing an abrupt connection between quantum dots. Asymmetric Fano lines are characterized by the close coexistence of resonant enhancement and resonant suppression. Therefore, we pay particular attention to voltages, which in the static case, correspond to both these features. Our research shows that the analyzed resonances are characterized by two time scales: (i) the first one related to charge oscillations between subsystems and mostly governed by the interdot coupling constant and the relative position of energy levels of quantum dots, and (ii) the second one associated to the electron scattering on a continuum of states and responsible for the relaxation. We also show that the time required for achieving a static solution is different for voltages corresponding to local minima and local maxima. Close http://appol.ifpan.edu.pl/index.php/appa/article/view/143_143 Close
2022
135.	Ye-Hong Chen, Adam Miranowicz, Xi Chen, Yan Xia, Franco Nori Enhanced-Fidelity Ultrafast Geometric Quantum Computation Using Strong Classical Drives Phys. Rev. Appl., 18 , pp. 064059, 2022. Abstract \| Links \| BibTeX @article{Chen22geom, title = {Enhanced-Fidelity Ultrafast Geometric Quantum Computation Using Strong Classical Drives}, author = {Ye-Hong Chen and Adam Miranowicz and Xi Chen and Yan Xia and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.18.064059}, doi = {10.1103/PhysRevApplied.18.064059}, year = {2022}, date = {2022-12-20}, journal = {Phys. Rev. Appl.}, volume = {18}, pages = {064059}, publisher = {American Physical Society}, abstract = {We propose a general approach to implement ultrafast nonadiabatic geometric single- and two-qubit gates by employing counter-rotating effects. This protocol is compatible with most optimal control methods used in previous rotating-wave approximation (RWA) protocols; thus, it is as robust as (or even more robust than) the RWA protocols. Using counter-rotating effects allows us to apply strong drives. Therefore, we can improve the gate speed by 5–10 times compared to the RWA counterpart for implementing high-fidelity (≥99.99%) gates. Such an ultrafast evolution (nanoseconds, even picoseconds) significantly reduces the influence of decoherence (e.g., the qubit dissipation and dephasing). Moreover, because the counter-rotating effects no longer induce a gate infidelity (in both the weak and strong driving regimes), we can achieve a higher fidelity compared to the RWA protocols. Therefore, in the presence of decoherence, one can implement ultrafast geometric quantum gates with ≥99% fidelities.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We propose a general approach to implement ultrafast nonadiabatic geometric single- and two-qubit gates by employing counter-rotating effects. This protocol is compatible with most optimal control methods used in previous rotating-wave approximation (RWA) protocols; thus, it is as robust as (or even more robust than) the RWA protocols. Using counter-rotating effects allows us to apply strong drives. Therefore, we can improve the gate speed by 5–10 times compared to the RWA counterpart for implementing high-fidelity (≥99.99%) gates. Such an ultrafast evolution (nanoseconds, even picoseconds) significantly reduces the influence of decoherence (e.g., the qubit dissipation and dephasing). Moreover, because the counter-rotating effects no longer induce a gate infidelity (in both the weak and strong driving regimes), we can achieve a higher fidelity compared to the RWA protocols. Therefore, in the presence of decoherence, one can implement ultrafast geometric quantum gates with ≥99% fidelities. Close https://link.aps.org/doi/10.1103/PhysRevApplied.18.064059 doi:10.1103/PhysRevApplied.18.064059 Close
134.	Irina Werner, Jan Griebel, Albert Masip-Sánchez, Xavier López, Karol Załęski, Piotr Kozłowski, Axel Kahnt, Martin Boerner, Ziyan Warneke, Jonas Warneke, Kirill Yu. Monakhov Hybrid Molecular Magnets with Lanthanide- and Countercation-Mediated Interfacial Electron Transfer between Phthalocyanine and Polyoxovanadate Inorganic Chemistry, 62 (9), pp. 3761-3775, 2022, (PMID: 36534941). Links \| BibTeX @article{doi:10.1021/acs.inorgchem.2c03599, title = {Hybrid Molecular Magnets with Lanthanide- and Countercation-Mediated Interfacial Electron Transfer between Phthalocyanine and Polyoxovanadate}, author = {Irina Werner and Jan Griebel and Albert Masip-Sánchez and Xavier López and Karol Załęski and Piotr Kozłowski and Axel Kahnt and Martin Boerner and Ziyan Warneke and Jonas Warneke and Kirill Yu. Monakhov}, url = {https://doi.org/10.1021/acs.inorgchem.2c03599}, doi = {10.1021/acs.inorgchem.2c03599}, year = {2022}, date = {2022-12-19}, journal = {Inorganic Chemistry}, volume = {62}, number = {9}, pages = {3761-3775}, note = {PMID: 36534941}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://doi.org/10.1021/acs.inorgchem.2c03599 doi:10.1021/acs.inorgchem.2c03599 Close
133.	Jan Perina Jr, Adam Miranowicz, Grzegorz Chimczak, Anna Kowalewska-Kudłaszyk Quantum Liouvillian exceptional and diabolical points for bosonic fields with quadratic Ħamiltonians: Ŧhe Ħeisenberg-Langevin equation approach Quantum, 6 , pp. 883, 2022, ISSN: 2521-327X. Abstract \| Links \| BibTeX @article{Perina2022quantum, title = {Quantum Liouvillian exceptional and diabolical points for bosonic fields with quadratic Ħamiltonians: Ŧhe Ħeisenberg-Langevin equation approach}, author = {Jan Perina Jr and Adam Miranowicz and Grzegorz Chimczak and Anna Kowalewska-Kudłaszyk}, url = {https://doi.org/10.22331/q-2022-12-22-883}, doi = {10.22331/q-2022-12-22-883}, issn = {2521-327X}, year = {2022}, date = {2022-12-10}, journal = {Quantum}, volume = {6}, pages = {883}, publisher = {Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften}, abstract = {Equivalent approaches to determine eigenfrequencies of the Liouvillians of open quantum systems are discussed using the solution of the Heisenberg-Langevin equations and the corresponding equations for operator moments. A simple damped two-level atom is analyzed to demonstrate the equivalence of both approaches. The suggested method is used to reveal the structure as well as eigenfrequencies of the dynamics matrices of the corresponding equations of motion and their degeneracies for interacting bosonic modes described by general quadratic Hamiltonians. Quantum Liouvillian exceptional and diabolical points and their degeneracies are explicitly discussed for the case of two modes. Quantum hybrid diabolical exceptional points (inherited, genuine, and induced) and hidden exceptional points, which are not recognized directly in amplitude spectra, are observed. The presented approach via the Heisenberg-Langevin equations paves the general way to a detailed analysis of quantum exceptional and diabolical points in infinitely dimensional open quantum systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Equivalent approaches to determine eigenfrequencies of the Liouvillians of open quantum systems are discussed using the solution of the Heisenberg-Langevin equations and the corresponding equations for operator moments. A simple damped two-level atom is analyzed to demonstrate the equivalence of both approaches. The suggested method is used to reveal the structure as well as eigenfrequencies of the dynamics matrices of the corresponding equations of motion and their degeneracies for interacting bosonic modes described by general quadratic Hamiltonians. Quantum Liouvillian exceptional and diabolical points and their degeneracies are explicitly discussed for the case of two modes. Quantum hybrid diabolical exceptional points (inherited, genuine, and induced) and hidden exceptional points, which are not recognized directly in amplitude spectra, are observed. The presented approach via the Heisenberg-Langevin equations paves the general way to a detailed analysis of quantum exceptional and diabolical points in infinitely dimensional open quantum systems. Close https://doi.org/10.22331/q-2022-12-22-883 doi:10.22331/q-2022-12-22-883 Close
132.	Mathieu Moalic, Maciej Krawczyk, Mateusz Zelent Spin-wave spectra in antidot lattice with inhomogeneous perpendicular magnetic anisotropy Journal of Applied Physics, 132 (21), pp. 213901, 2022. Abstract \| Links \| BibTeX @article{doi:10.1063/5.0128621, title = {Spin-wave spectra in antidot lattice with inhomogeneous perpendicular magnetic anisotropy}, author = {Mathieu Moalic and Maciej Krawczyk and Mateusz Zelent}, url = {https://doi.org/10.1063/5.0128621}, doi = {10.1063/5.0128621}, year = {2022}, date = {2022-12-01}, journal = {Journal of Applied Physics}, volume = {132}, number = {21}, pages = {213901}, abstract = {Magnonic crystals are structures with periodically varied magnetic properties that are used to control collective spin-wave excitations. With micromagnetic simulations, we study spin-wave spectra in a 2D antidot lattice based on a multilayered thin film with perpendicular magnetic anisotropy (PMA). We show that the modification of the PMA near the antidot edges introduces interesting changes to the spin-wave spectra, even in a fully saturated state. In particular, the spectra split into two types of excitations: bulk modes with amplitude concentrated in a homogeneous part of the antidot lattice and edge modes with an amplitude localized in the rims of reduced PMA at the antidot edges. Their dependence on the geometrical or material parameters is distinct, but at resonance conditions fulfilled, we found strong hybridization between bulk and radial edge modes. Interestingly, the hybridization between the fundamental modes in bulk and rim is of magnetostatic origin, but the exchange interactions determine the coupling between higher-order radial rim modes and the fundamental bulk mode of the antidot lattice.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnonic crystals are structures with periodically varied magnetic properties that are used to control collective spin-wave excitations. With micromagnetic simulations, we study spin-wave spectra in a 2D antidot lattice based on a multilayered thin film with perpendicular magnetic anisotropy (PMA). We show that the modification of the PMA near the antidot edges introduces interesting changes to the spin-wave spectra, even in a fully saturated state. In particular, the spectra split into two types of excitations: bulk modes with amplitude concentrated in a homogeneous part of the antidot lattice and edge modes with an amplitude localized in the rims of reduced PMA at the antidot edges. Their dependence on the geometrical or material parameters is distinct, but at resonance conditions fulfilled, we found strong hybridization between bulk and radial edge modes. Interestingly, the hybridization between the fundamental modes in bulk and rim is of magnetostatic origin, but the exchange interactions determine the coupling between higher-order radial rim modes and the fundamental bulk mode of the antidot lattice. Close https://doi.org/10.1063/5.0128621 doi:10.1063/5.0128621 Close
131.	Justyna Rychły-Gruszecka, Jakob Walowski, Christian Denker, Tobias Tubandt, Markus Munzenberg, Jarosław W. Kłos Shaping the spin wave spectra of planar 1D magnonic crystals by the geometrical constraints Scientific Reports, 12 (1), pp. 20678, 2022, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{Rychły-Gruszecka2022, title = {Shaping the spin wave spectra of planar 1D magnonic crystals by the geometrical constraints}, author = {Justyna Rychły-Gruszecka and Jakob Walowski and Christian Denker and Tobias Tubandt and Markus Munzenberg and Jarosław W. Kłos}, url = {https://doi.org/10.1038/s41598-022-24969-x}, doi = {10.1038/s41598-022-24969-x}, issn = {2045-2322}, year = {2022}, date = {2022-11-30}, journal = {Scientific Reports}, volume = {12}, number = {1}, pages = {20678}, abstract = {We present experimental and numerical studies demonstrating the influence of geometrical parameters on the fundamental spin-wave mode in planar 1D magnonic crystals. The investigated magnonic crystals consist of flat stripes separated by air gaps. The adjustment of geometrical parameters allows tailoring of the spin-wave frequencies. The width of stripes and the width of gaps between them affect spin-wave frequencies in two ways. First, directly by geometrical constraints confining the spin waves inside the stripes. Second, indirectly by spin-wave pinning, freeing the spin waves to a different extent on the edges of stripes. Experimentally, the fundamental spin-wave mode frequencies are measured using an all-optical pump-probe time-resolved magneto-optical Kerr-effect setup. Our studies address the problem of spin-wave confinement and spin-wave dipolar pinning in an array of coupled stripes. We show that the frequency of fundamental mode can be tuned to a large extent by adjusting the width of the stripes and the width of gaps between them.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We present experimental and numerical studies demonstrating the influence of geometrical parameters on the fundamental spin-wave mode in planar 1D magnonic crystals. The investigated magnonic crystals consist of flat stripes separated by air gaps. The adjustment of geometrical parameters allows tailoring of the spin-wave frequencies. The width of stripes and the width of gaps between them affect spin-wave frequencies in two ways. First, directly by geometrical constraints confining the spin waves inside the stripes. Second, indirectly by spin-wave pinning, freeing the spin waves to a different extent on the edges of stripes. Experimentally, the fundamental spin-wave mode frequencies are measured using an all-optical pump-probe time-resolved magneto-optical Kerr-effect setup. Our studies address the problem of spin-wave confinement and spin-wave dipolar pinning in an array of coupled stripes. We show that the frequency of fundamental mode can be tuned to a large extent by adjusting the width of the stripes and the width of gaps between them. Close https://doi.org/10.1038/s41598-022-24969-x doi:10.1038/s41598-022-24969-x Close
130.	Andriy E. Serebryannikov, Akhlesh Lakhtakia, Ekmel Ozbay Thermally switchable, bifunctional, scalable, mid-infrared metasurfaces with VO2 grids capable of versatile polarization manipulation and asymmetric transmission Opt. Mater. Express, 12 (12), pp. 4594–4605, 2022. Abstract \| Links \| BibTeX @article{Serebryannikov:22, title = {Thermally switchable, bifunctional, scalable, mid-infrared metasurfaces with VO2 grids capable of versatile polarization manipulation and asymmetric transmission}, author = {Andriy E. Serebryannikov and Akhlesh Lakhtakia and Ekmel Ozbay}, url = {https://opg.optica.org/ome/abstract.cfm?URI=ome-12-12-4594}, doi = {10.1364/OME.465468}, year = {2022}, date = {2022-11-16}, journal = {Opt. Mater. Express}, volume = {12}, number = {12}, pages = {4594--4605}, publisher = {Optica Publishing Group}, abstract = {We conceptualized three-array scalable bifunctional metasurfaces comprising only three thin strip grids and numerically determined their characteristics in the mid-infrared spectral regime for switchable operation scenarios involving polarization manipulation and related diodelike asymmetric transmission (AT) as one of two functionalities. A few or all of the grids were taken to be made of VO2, a bifunctionality-enabling phase-change material; there are no layers and/or meta-atoms comprising simultaneously both metal and VO2. For each proposed metasurface, two effective structures and, therefore, two different functionalities exist, corresponding to the metallic and insulating phases of VO2. The achieved scenarios of functionality switching significantly depend on the way in which VO2 is incorporated into the metasurface. Switchable bands of polarization manipulation are up to 40 THz wide. The AT band can be modulated when Fabry–Perot (anti-) resonances come into play. Besides, transmission regimes with the cross-polarized component insensitive to VO2 phase change are possible, as well as the ones with all co- and cross-polarized components having the same magnitude for both linear polarizations of the incident wave.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We conceptualized three-array scalable bifunctional metasurfaces comprising only three thin strip grids and numerically determined their characteristics in the mid-infrared spectral regime for switchable operation scenarios involving polarization manipulation and related diodelike asymmetric transmission (AT) as one of two functionalities. A few or all of the grids were taken to be made of VO2, a bifunctionality-enabling phase-change material; there are no layers and/or meta-atoms comprising simultaneously both metal and VO2. For each proposed metasurface, two effective structures and, therefore, two different functionalities exist, corresponding to the metallic and insulating phases of VO2. The achieved scenarios of functionality switching significantly depend on the way in which VO2 is incorporated into the metasurface. Switchable bands of polarization manipulation are up to 40 THz wide. The AT band can be modulated when Fabry–Perot (anti-) resonances come into play. Besides, transmission regimes with the cross-polarized component insensitive to VO2 phase change are possible, as well as the ones with all co- and cross-polarized components having the same magnitude for both linear polarizations of the incident wave. Close https://opg.optica.org/ome/abstract.cfm?URI=ome-12-12-4594 doi:10.1364/OME.465468 Close
129.	Tymoteusz Salamon, Bernhard Irsigler, Debraj Rakshit, Maciej Lewenstein, Tobias Grass, Ravindra W. Chhajlany Flat-band-induced superconductivity in synthetic bilayer optical lattices Phys. Rev. B, 106 , pp. 174503, 2022. Abstract \| Links \| BibTeX @article{PhysRevB.106.174503, title = {Flat-band-induced superconductivity in synthetic bilayer optical lattices}, author = {Tymoteusz Salamon and Bernhard Irsigler and Debraj Rakshit and Maciej Lewenstein and Tobias Grass and Ravindra W. Chhajlany}, url = {https://link.aps.org/doi/10.1103/PhysRevB.106.174503}, doi = {10.1103/PhysRevB.106.174503}, year = {2022}, date = {2022-11-04}, journal = {Phys. Rev. B}, volume = {106}, pages = {174503}, publisher = {American Physical Society}, abstract = {Stacking two layers of graphene with a relative twist angle gives rise to Moiré patterns, which can strongly modify electronic behavior and may lead to unconventional superconductivity. A synthetic version of twisted bilayers can be engineered with cold atoms in optical lattices. Here, the bilayer structure is mimicked through coupling between atomic sublevels, and the twist is achieved by a spatial modulation of this coupling. In the present paper, we investigate the superconducting behavior of fermionic atoms in such a synthetic twisted bilayer lattice. Attractive interactions between the atoms are treated on the mean-field level, and the superconducting behavior is analyzed via the self-consistently determined pairing gap. A strong enhancement of the pairing gap is found when a quasi-flat band structure occurs at the Fermi surface, reflecting the prominent role played by the twist on the superconductivity. The tunability of interactions allows for the switching of superconducting correlations from intra (synthetic) layer to inter (synthetic) layer. This includes also the intermediate scenario, in which the competition between inter- and intra-layer coupling completely destroys the superconducting behavior, resulting in re-entrant superconductivity upon tuning of the interactions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Stacking two layers of graphene with a relative twist angle gives rise to Moiré patterns, which can strongly modify electronic behavior and may lead to unconventional superconductivity. A synthetic version of twisted bilayers can be engineered with cold atoms in optical lattices. Here, the bilayer structure is mimicked through coupling between atomic sublevels, and the twist is achieved by a spatial modulation of this coupling. In the present paper, we investigate the superconducting behavior of fermionic atoms in such a synthetic twisted bilayer lattice. Attractive interactions between the atoms are treated on the mean-field level, and the superconducting behavior is analyzed via the self-consistently determined pairing gap. A strong enhancement of the pairing gap is found when a quasi-flat band structure occurs at the Fermi surface, reflecting the prominent role played by the twist on the superconductivity. The tunability of interactions allows for the switching of superconducting correlations from intra (synthetic) layer to inter (synthetic) layer. This includes also the intermediate scenario, in which the competition between inter- and intra-layer coupling completely destroys the superconducting behavior, resulting in re-entrant superconductivity upon tuning of the interactions. Close https://link.aps.org/doi/10.1103/PhysRevB.106.174503 doi:10.1103/PhysRevB.106.174503 Close
128.	Mateusz Zelent, Paweł Gruszecki, Mathieu Moalic, Olav Hellwig, Anjan Barman, Maciej Krawczyk Spin dynamics in patterned magnetic multilayers with perpendicular magnetic anisotropy Macedo, Rair (Ed.): 73 , pp. 1-51, Academic Press, 2022, ISSN: 0081-1947. Abstract \| Links \| BibTeX @incollection{ZELENT20221, title = {Spin dynamics in patterned magnetic multilayers with perpendicular magnetic anisotropy}, author = {Mateusz Zelent and Paweł Gruszecki and Mathieu Moalic and Olav Hellwig and Anjan Barman and Maciej Krawczyk}, editor = {Rair Macedo}, url = {https://www.sciencedirect.com/science/article/pii/S0081194722000029}, doi = {https://doi.org/10.1016/bs.ssp.2022.08.002}, issn = {0081-1947}, year = {2022}, date = {2022-10-27}, volume = {73}, pages = {1-51}, publisher = {Academic Press}, series = {Solid State Physics}, abstract = {The magnetization dynamics in nanostructures has been extensively studied in the last decades, and nanomagnetism has evolved significantly over that time, discovering new effects, developing numerous applications, and identifying promising new directions. This includes magnonics, an emerging research field oriented on the study of spin-wave dynamics and their applications. In this context, thin ferromagnetic films with perpendicular magnetic anisotropy (PMA) offer interesting opportunities to study spin waves, in particular, due to out-of-plane magnetization in remanence or at relatively weak external magnetic fields. This is the only magnetization configuration offering isotropic in-plane spin-wave propagation within the sample plane, the forward volume magnetostatic spin-wave geometry. The isotropic dispersion relation is highly important in designing signal-processing devices, offering superior prospects for direct replicating various concepts from photonics into magnonics. Analogous to photonic or phononic crystals, which are the building blocks of optoelectronics and phononics, magnonic crystals are considered as key components in magnonics applications. Arrays of nanodots and structured ferromagnetic thin films with a periodic array of holes, popularly known as antidot lattices based on PMA multilayers, have been recently studied. Novel magnonic properties related to propagating spin-wave modes, exploitation of the band gaps, and confined modes were demonstrated. Also, the existence of nontrivial magnonic band topologies has been shown. Moreover, the combination of PMA and Dzyaloshinskii–Moriya interaction leads to the formation of chiral magnetization states, including Néel domain walls, skyrmions, and skyrmionium states. This promotes the multilayers with PMA as an interesting topic for magnonics and this chapter reviews the background and attempts to provide future perspectives in this research field.}, keywords = {}, pubstate = {published}, tppubtype = {incollection} } Close The magnetization dynamics in nanostructures has been extensively studied in the last decades, and nanomagnetism has evolved significantly over that time, discovering new effects, developing numerous applications, and identifying promising new directions. This includes magnonics, an emerging research field oriented on the study of spin-wave dynamics and their applications. In this context, thin ferromagnetic films with perpendicular magnetic anisotropy (PMA) offer interesting opportunities to study spin waves, in particular, due to out-of-plane magnetization in remanence or at relatively weak external magnetic fields. This is the only magnetization configuration offering isotropic in-plane spin-wave propagation within the sample plane, the forward volume magnetostatic spin-wave geometry. The isotropic dispersion relation is highly important in designing signal-processing devices, offering superior prospects for direct replicating various concepts from photonics into magnonics. Analogous to photonic or phononic crystals, which are the building blocks of optoelectronics and phononics, magnonic crystals are considered as key components in magnonics applications. Arrays of nanodots and structured ferromagnetic thin films with a periodic array of holes, popularly known as antidot lattices based on PMA multilayers, have been recently studied. Novel magnonic properties related to propagating spin-wave modes, exploitation of the band gaps, and confined modes were demonstrated. Also, the existence of nontrivial magnonic band topologies has been shown. Moreover, the combination of PMA and Dzyaloshinskii–Moriya interaction leads to the formation of chiral magnetization states, including Néel domain walls, skyrmions, and skyrmionium states. This promotes the multilayers with PMA as an interesting topic for magnonics and this chapter reviews the background and attempts to provide future perspectives in this research field. Close https://www.sciencedirect.com/science/article/pii/S0081194722000029 doi:https://doi.org/10.1016/bs.ssp.2022.08.002 Close
127.	Aleksey Girich, Liubov Ivzhenko, Artem Hrinchenko, Sergey Tarapov, Oleh Yermakov Manipulation Over Surface Waves in Bilayer Hyperbolic Metasurfaces: Topological Transition and Multidirectional Canalization IEEE Microwave and Wireless Components Letters, pp. 1-4, 2022. Abstract \| Links \| BibTeX @article{9931333, title = {Manipulation Over Surface Waves in Bilayer Hyperbolic Metasurfaces: Topological Transition and Multidirectional Canalization}, author = {Aleksey Girich and Liubov Ivzhenko and Artem Hrinchenko and Sergey Tarapov and Oleh Yermakov}, doi = {10.1109/LMWC.2022.3215016}, year = {2022}, date = {2022-10-27}, journal = {IEEE Microwave and Wireless Components Letters}, pages = {1-4}, abstract = {Spoof surface plasmon-polariton is a type of surface wave (SW) propagating at the artificially engineered structures in microwave and terahertz ranges. These SWs are highly important in planar photonic and on-chip devices, integrated circuits, lenses, sensors, and antennas applications. However, it is still a challenge to control the propagation regime of such SWs including the wavefront shapes and propagation directions. In this letter, we study the SWs in bilayer hyperbolic metasurfaces and show that the interplay between two layers allows them to manage their regime of propagation. We demonstrate the switching between the angle and number of propagation directions of SWs at the same frequency. Finally, we demonstrate experimentally the tunable multidirectional in-plane canalization of SWs by adjusting the directions of their propagation within the angular range from 0 to 12.8 deg. The discovered rotation-mediated interlayer coupling of hyperbolic metasurfaces paves the way toward efficient in-plane transfer of localized electromagnetic signals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spoof surface plasmon-polariton is a type of surface wave (SW) propagating at the artificially engineered structures in microwave and terahertz ranges. These SWs are highly important in planar photonic and on-chip devices, integrated circuits, lenses, sensors, and antennas applications. However, it is still a challenge to control the propagation regime of such SWs including the wavefront shapes and propagation directions. In this letter, we study the SWs in bilayer hyperbolic metasurfaces and show that the interplay between two layers allows them to manage their regime of propagation. We demonstrate the switching between the angle and number of propagation directions of SWs at the same frequency. Finally, we demonstrate experimentally the tunable multidirectional in-plane canalization of SWs by adjusting the directions of their propagation within the angular range from 0 to 12.8 deg. The discovered rotation-mediated interlayer coupling of hyperbolic metasurfaces paves the way toward efficient in-plane transfer of localized electromagnetic signals. Close doi:10.1109/LMWC.2022.3215016 Close
126.	Maciej Lewenstein, David Cirauqui, Miguel Angel Garcia-March, Guillem Guigo i Corominas, Przemysław R. Grzybowski, Jose Saavedra, Martin Wilkens, Jan Wehr Haake-Lewenstein-Wilkens approach to spin-glasses revisited Journal of Physics A: Mathematical and Theoretical, 2022. Abstract \| Links \| BibTeX @article{10.1088/1751-8121/ac9d10b, title = {Haake-Lewenstein-Wilkens approach to spin-glasses revisited}, author = {Maciej Lewenstein and David Cirauqui and Miguel Angel Garcia-March and Guillem Guigo i Corominas and Przemysław R. Grzybowski and Jose Saavedra and Martin Wilkens and Jan Wehr}, url = {http://iopscience.iop.org/article/10.1088/1751-8121/ac9d10}, year = {2022}, date = {2022-10-24}, journal = {Journal of Physics A: Mathematical and Theoretical}, abstract = {We revisit the Haake-Lewenstein-Wilkens (HLW) approach to Edwards-Anderson (EA) model of Ising spin glass [Phys. Rev. Lett. 55, 2606 (1985)]. This approach consists in evaluation and analysis of the probability distribution of conﬁgurations of two replicas of the system, averaged over quenched disorder. This probability This approximate result suggest that qEA > 0 at 0 < T < Tc in 3D and 4D. The case of 2D seems to be a little more subtle, since in the present approach energy increase for a domain wall competes with boundary/edge effects more strongly in 2D; still our approach predicts spin glass order at sufﬁciently low temperature. We speculate, how these predictions conﬁrm/contradict widely spread opinions that: i) There exist only one (up to the spin ﬂip) ground state in EA model in 2D, 3D and 4D; ii) There is (no) spin glass transition in 3D and 4D (2D). This paper is dedicated to the memories of Fritz Haake and Marek Cieplak.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We revisit the Haake-Lewenstein-Wilkens (HLW) approach to Edwards-Anderson (EA) model of Ising spin glass [Phys. Rev. Lett. 55, 2606 (1985)]. This approach consists in evaluation and analysis of the probability distribution of conﬁgurations of two replicas of the system, averaged over quenched disorder. This probability This approximate result suggest that qEA > 0 at 0 < T < Tc in 3D and 4D. The case of 2D seems to be a little more subtle, since in the present approach energy increase for a domain wall competes with boundary/edge effects more strongly in 2D; still our approach predicts spin glass order at sufﬁciently low temperature. We speculate, how these predictions conﬁrm/contradict widely spread opinions that: i) There exist only one (up to the spin ﬂip) ground state in EA model in 2D, 3D and 4D; ii) There is (no) spin glass transition in 3D and 4D (2D). This paper is dedicated to the memories of Fritz Haake and Marek Cieplak. Close http://iopscience.iop.org/article/10.1088/1751-8121/ac9d10 Close
125.	Shilan Abo, Grzegorz Chimczak, Anna Kowalewska-Kudłaszyk, Jan Peřina Jr, Ravindra W. Chhajlany, Adam Miranowicz Hybrid photon–phonon blockade Scientific Reports, 12 , pp. 17655, 2022, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{shilan2022, title = {Hybrid photon–phonon blockade}, author = {Shilan Abo and Grzegorz Chimczak and Anna Kowalewska-Kudłaszyk and Jan Peřina Jr and Ravindra W. Chhajlany and Adam Miranowicz }, url = {https://www.nature.com/articles/s41598-022-21267-4}, doi = {https://doi.org/10.1038/s41598-022-21267-4}, issn = {2045-2322}, year = {2022}, date = {2022-10-21}, journal = {Scientific Reports}, volume = {12}, pages = {17655}, abstract = {We describe a novel type of blockade in a hybrid mode generated by linear coupling of photonic and phononic modes. We refer to this effect as hybrid photon–phonon blockade and show how it can be generated and detected in a driven nonlinear optomechanical superconducting system. Thus, we study boson-number correlations in the photon, phonon, and hybrid modes in linearly coupled microwave and mechanical resonators with a superconducting qubit inserted in one of them. We find such system parameters for which we observe eight types of different combinations of either blockade or tunnelling effects (defined via the sub- and super-Poissonian statistics, respectively) for photons, phonons, and hybrid bosons. In particular, we find that the hybrid photon–phonon blockade can be generated by mixing the photonic and phononic modes which do not exhibit blockade.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We describe a novel type of blockade in a hybrid mode generated by linear coupling of photonic and phononic modes. We refer to this effect as hybrid photon–phonon blockade and show how it can be generated and detected in a driven nonlinear optomechanical superconducting system. Thus, we study boson-number correlations in the photon, phonon, and hybrid modes in linearly coupled microwave and mechanical resonators with a superconducting qubit inserted in one of them. We find such system parameters for which we observe eight types of different combinations of either blockade or tunnelling effects (defined via the sub- and super-Poissonian statistics, respectively) for photons, phonons, and hybrid bosons. In particular, we find that the hybrid photon–phonon blockade can be generated by mixing the photonic and phononic modes which do not exhibit blockade. Close https://www.nature.com/articles/s41598-022-21267-4 doi:https://doi.org/10.1038/s41598-022-21267-4 Close
124.	E.S. Gevorkyan, V.P. Nerubatskyi, R.V. Vovk, V.O. Chyshkala, S.V. Lytovchenko, O.M. Morozova, Jolanta Natalia Latosińska Features of synthesis of Y2Ti2O7 ceramics for the purpose of obtaining dispersion-strengthened steels Acta Physica Polonica A, 142 (4), pp. 529, 2022. Abstract \| Links \| BibTeX @article{latosinska2022, title = {Features of synthesis of Y2Ti2O7 ceramics for the purpose of obtaining dispersion-strengthened steels}, author = {E.S. Gevorkyan and V.P. Nerubatskyi and R.V. Vovk and V.O. Chyshkala and S.V. Lytovchenko and O.M. Morozova and Jolanta Natalia Latosińska}, url = {http://przyrbwn.icm.edu.pl/APP/SPIS/a142-4.html}, doi = {10.12693/APhysPolA.142.529}, year = {2022}, date = {2022-10-17}, journal = {Acta Physica Polonica A}, volume = {142}, number = {4}, pages = {529}, abstract = {The method of electron beam heating of a mixture of yttrium and zirconium oxides for the synthesis of complex oxides has been implemented. It is established that the applied technology of melting the mixture of oxides leads to the formation of fluorite phases. It is determined that homogenization of the initial mixture of oxides should be carried out in a high-energy mill, which will reduce the temperature and duration of the synthesis of complex oxide compounds, including the desired structure of pyrochlorine. It is proposed to improve the technique of intensive thermal influence on the process of pyrochlorine synthesis by using an equiatomic alloy Y-Ti (65 wt. Y-35 wt Ti), which has been smelted using the arc melting method in an argon atmosphere. It was found that hydrogen saturation reduces the efficiency of pyrochlorine synthesis and increases the grain size, which may be associated with grain growth at the stage of hydrogen saturation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The method of electron beam heating of a mixture of yttrium and zirconium oxides for the synthesis of complex oxides has been implemented. It is established that the applied technology of melting the mixture of oxides leads to the formation of fluorite phases. It is determined that homogenization of the initial mixture of oxides should be carried out in a high-energy mill, which will reduce the temperature and duration of the synthesis of complex oxide compounds, including the desired structure of pyrochlorine. It is proposed to improve the technique of intensive thermal influence on the process of pyrochlorine synthesis by using an equiatomic alloy Y-Ti (65 wt. Y-35 wt Ti), which has been smelted using the arc melting method in an argon atmosphere. It was found that hydrogen saturation reduces the efficiency of pyrochlorine synthesis and increases the grain size, which may be associated with grain growth at the stage of hydrogen saturation. Close http://przyrbwn.icm.edu.pl/APP/SPIS/a142-4.html doi:10.12693/APhysPolA.142.529 Close

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