List of publications
Department of Mesoscopic Physics
Department of Nonlinear Optics
Department of Physics of Nanostructures
Department of Theory of Condensed Matter
2025 |
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| 288. | Mateusz Gołębiewski, Krzysztof Szulc, Maciej Krawczyk Magnetic field controlled surface localization of ferromagnetic resonance modes in 3D nanostructures Acta Materialia, 283 , pp. 120499, 2025, ISSN: 1359-6454. @article{GOLEBIEWSKI2025120499, title = {Magnetic field controlled surface localization of ferromagnetic resonance modes in 3D nanostructures}, author = {Mateusz Gołębiewski and Krzysztof Szulc and Maciej Krawczyk}, url = {https://www.sciencedirect.com/science/article/pii/S1359645424008486}, doi = {https://doi.org/10.1016/j.actamat.2024.120499}, issn = {1359-6454}, year = {2025}, date = {2025-01-15}, journal = {Acta Materialia}, volume = {283}, pages = {120499}, abstract = {By extending the current understanding and use of magnonics beyond conventional planar systems, we demonstrate the surface localization of ferromagnetic resonance (FMR) modes through the design of complex three-dimensional nanostructures. Using micromagnetic simulations, we systematically investigate woodpile-like scaffolds and gyroids — periodic chiral entities characterized by their triple junctions. The study highlights the critical role of demagnetizing fields and exchange energy in determining the FMR responses of 3D nanosystems, especially the strongly asymmetric distribution of the spin-wave mode over the system’s height. Importantly, the top–bottom dynamic switching of the surface mode localization across the structures in response to changes in magnetic field orientation provides a new method for controlling magnetization dynamics. The results demonstrate the critical role of the geometric features in dictating the dynamic magnetic behavior of three-dimensional nanostructures, paving the way for both experimental exploration and practical advances in 3D magnonics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } By extending the current understanding and use of magnonics beyond conventional planar systems, we demonstrate the surface localization of ferromagnetic resonance (FMR) modes through the design of complex three-dimensional nanostructures. Using micromagnetic simulations, we systematically investigate woodpile-like scaffolds and gyroids — periodic chiral entities characterized by their triple junctions. The study highlights the critical role of demagnetizing fields and exchange energy in determining the FMR responses of 3D nanosystems, especially the strongly asymmetric distribution of the spin-wave mode over the system’s height. Importantly, the top–bottom dynamic switching of the surface mode localization across the structures in response to changes in magnetic field orientation provides a new method for controlling magnetization dynamics. The results demonstrate the critical role of the geometric features in dictating the dynamic magnetic behavior of three-dimensional nanostructures, paving the way for both experimental exploration and practical advances in 3D magnonics. |
2024 |
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| 287. | P Graczyk, Bivas Rana, Aleksandra Trzaskowska, B K Mahato, Jarosław W. Kłos, Maciej Krawczyk, A Barman Ultrasonics, 148 , pp. 107522, 2024, ISSN: 0041-624X. @article{GRACZYK2025107522, title = {Optical excitation and detection of high-frequency Sezawa modes in Si/SiO2 system decorated with Ni80Fe20 nanodot arrays}, author = {P Graczyk and Bivas Rana and Aleksandra Trzaskowska and B K Mahato and Jarosław W. Kłos and Maciej Krawczyk and A Barman}, url = {https://www.sciencedirect.com/science/article/pii/S0041624X24002853}, doi = {https://doi.org/10.1016/j.ultras.2024.107522}, issn = {0041-624X}, year = {2024}, date = {2024-12-04}, journal = {Ultrasonics}, volume = {148}, pages = {107522}, abstract = {Surface acoustic waves have emerged as one of the potential candidates for the development of next-generation wave-based information and computing technologies. For practical devices, it is essential to develop the excitation techniques for different types of surface acoustic waves, especially at higher microwave frequencies, and to tailor their frequency versus wave vector characteristics. We show that this can be done by using ultrashort laser pulses incident on the surface of a multilayer decorated with a periodic array of metallic nanodots. Specifically, we study surface acoustic waves in the dielectric substrate Si/SiO2 decorated with a square lattice of thin Ni80Fe20 (Py) dots. Using a femtosecond laser-based optical pump–probe measurement, we detect a number of high-frequency phononic modes. By performing finite element simulations, we identify them as Sezawa modes from the second and third Brillouin zone in addition to the modes confined within the Py dots. The frequency of the Sezawa modes strongly depends on the period of the Py dots and varies in the range between 5 to 15 GHz. Both types of waves cover the same frequency range for Py dots with period less than 400 nm, providing a promising system for magnetoelastic studies.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Surface acoustic waves have emerged as one of the potential candidates for the development of next-generation wave-based information and computing technologies. For practical devices, it is essential to develop the excitation techniques for different types of surface acoustic waves, especially at higher microwave frequencies, and to tailor their frequency versus wave vector characteristics. We show that this can be done by using ultrashort laser pulses incident on the surface of a multilayer decorated with a periodic array of metallic nanodots. Specifically, we study surface acoustic waves in the dielectric substrate Si/SiO2 decorated with a square lattice of thin Ni80Fe20 (Py) dots. Using a femtosecond laser-based optical pump–probe measurement, we detect a number of high-frequency phononic modes. By performing finite element simulations, we identify them as Sezawa modes from the second and third Brillouin zone in addition to the modes confined within the Py dots. The frequency of the Sezawa modes strongly depends on the period of the Py dots and varies in the range between 5 to 15 GHz. Both types of waves cover the same frequency range for Py dots with period less than 400 nm, providing a promising system for magnetoelastic studies. |
| 286. | Xin Wang, Jia-Qi Li, Tao Liu, Adam Miranowicz, Franco Nori Long-range four-body interactions in structured nonlinear photonic waveguides Phys. Rev. Res., 6 , pp. 043226, 2024. @article{Wang24prr, title = {Long-range four-body interactions in structured nonlinear photonic waveguides}, author = {Xin Wang and Jia-Qi Li and Tao Liu and Adam Miranowicz and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevResearch.6.043226}, doi = {10.1103/PhysRevResearch.6.043226}, year = {2024}, date = {2024-12-01}, journal = {Phys. Rev. Res.}, volume = {6}, pages = {043226}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 285. | Wei Qin, Adam Miranowicz, Franco Nori Exponentially Improved Dispersive Qubit Readout with Squeezed Light Phys. Rev. Lett., 133 , pp. 233605, 2024. @article{Wei2024prr, title = {Exponentially Improved Dispersive Qubit Readout with Squeezed Light}, author = {Wei Qin and Adam Miranowicz and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevLett.133.233605}, doi = {10.1103/PhysRevLett.133.233605}, year = {2024}, date = {2024-12-01}, journal = {Phys. Rev. Lett.}, volume = {133}, pages = {233605}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 284. | Ryszard Gieniusz, Paweł Gruszecki, Jan Kisielewski, Anuj Kumar Dhiman, Michal Matczak, Zbigniew Kurant, Iosif Sveklo, Urszula Guzowska, Maria Tekielak, Maciej Krawczyk, Feliks Stobiecki, Andrzej Maziewski Spin wave frequency hysteresis in Ir/Co/Pt multilayers with Dzyaloshinskii-Moriya interaction Phys. Rev. B, 110 , pp. 184410, 2024. @article{PhysRevB.110.184410, title = {Spin wave frequency hysteresis in Ir/Co/Pt multilayers with Dzyaloshinskii-Moriya interaction}, author = {Ryszard Gieniusz and Paweł Gruszecki and Jan Kisielewski and Anuj Kumar Dhiman and Michal Matczak and Zbigniew Kurant and Iosif Sveklo and Urszula Guzowska and Maria Tekielak and Maciej Krawczyk and Feliks Stobiecki and Andrzej Maziewski}, url = {https://link.aps.org/doi/10.1103/PhysRevB.110.184410}, doi = {10.1103/PhysRevB.110.184410}, year = {2024}, date = {2024-11-14}, journal = {Phys. Rev. B}, volume = {110}, pages = {184410}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 283. | Bivas Rana, YoshiChika Otani Development of Magnonics with Voltage-Controlled Magnetic Anisotropy Bandyopadhyay, Supriyo, Barman, Anjan (Ed.): Nanomagnets as Dynamical Systems: Physics and Applications, pp. 71–96, Springer Nature Switzerland, Cham, 2024, ISBN: 978-3-031-73191-4. @inbook{Rana2024, title = {Development of Magnonics with Voltage-Controlled Magnetic Anisotropy}, author = {Bivas Rana and YoshiChika Otani}, editor = {Supriyo Bandyopadhyay and Anjan Barman}, url = {https://doi.org/10.1007/978-3-031-73191-4_3}, doi = {10.1007/978-3-031-73191-4_3}, isbn = {978-3-031-73191-4}, year = {2024}, date = {2024-11-10}, booktitle = {Nanomagnets as Dynamical Systems: Physics and Applications}, pages = {71--96}, publisher = {Springer Nature Switzerland}, address = {Cham}, abstract = {This chapter discusses the origin and essential features of interfacial magnetic anisotropies and voltage-controlled magnetic anisotropy (VCMAVoltage control of magnetic anisotropy (VCMA)) in ultrathin ferromagnetFerromagnet/oxide heterostructures. Various other electric field-induced methods for controlling magnetic properties and the advantages of VCMAVoltage control of magnetic anisotropy (VCMA) over them are thoroughly discussed. The recent progress of magnonics with VCMAVoltage control of magnetic anisotropy (VCMA) is described in detail. In particular, we discuss the linear and parametric excitation of ferromagnetic and spin waveSpin wave (SW) resonance; the essential properties of spin wavesSpin wave (SW) guided through reconfigurable nanochannels; the manipulation of spin waveSpin wave (SW) frequency, phase, wavevector, magnonic band structures, and damping parameters in detail. A brief discussion follows on the excitation and manipulation of spin wavesSpin wave (SW) by various other direct and indirect electric field-induced methods. The chapter concludes by briefly describing some open challenges in this field.}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } This chapter discusses the origin and essential features of interfacial magnetic anisotropies and voltage-controlled magnetic anisotropy (VCMAVoltage control of magnetic anisotropy (VCMA)) in ultrathin ferromagnetFerromagnet/oxide heterostructures. Various other electric field-induced methods for controlling magnetic properties and the advantages of VCMAVoltage control of magnetic anisotropy (VCMA) over them are thoroughly discussed. The recent progress of magnonics with VCMAVoltage control of magnetic anisotropy (VCMA) is described in detail. In particular, we discuss the linear and parametric excitation of ferromagnetic and spin waveSpin wave (SW) resonance; the essential properties of spin wavesSpin wave (SW) guided through reconfigurable nanochannels; the manipulation of spin waveSpin wave (SW) frequency, phase, wavevector, magnonic band structures, and damping parameters in detail. A brief discussion follows on the excitation and manipulation of spin wavesSpin wave (SW) by various other direct and indirect electric field-induced methods. The chapter concludes by briefly describing some open challenges in this field. |
| 282. | Sreedevi Janardhanan, Maciej Krawczyk, Aleksandra Trzaskowska Spin-Wave Dynamics in Ultra-thin Ferromagnetic Films, Patterned, and Non-patterned Bandyopadhyay, Supriyo, Barman, Anjan (Ed.): Nanomagnets as Dynamical Systems: Physics and Applications, pp. 33–69, Springer Nature Switzerland, Cham, 2024, ISBN: 978-3-031-73191-4. @inbook{Janardhanan2024b, title = {Spin-Wave Dynamics in Ultra-thin Ferromagnetic Films, Patterned, and Non-patterned}, author = {Sreedevi Janardhanan and Maciej Krawczyk and Aleksandra Trzaskowska}, editor = {Supriyo Bandyopadhyay and Anjan Barman}, url = {https://doi.org/10.1007/978-3-031-73191-4_2}, doi = {10.1007/978-3-031-73191-4_2}, isbn = {978-3-031-73191-4}, year = {2024}, date = {2024-11-10}, booktitle = {Nanomagnets as Dynamical Systems: Physics and Applications}, pages = {33--69}, publisher = {Springer Nature Switzerland}, address = {Cham}, abstract = {Exploring spin-waveSpin wave (SW) dynamics opens new avenues for technological applications across various fields. This chapter provides a comprehensive review of spin-waveSpin wave (SW) dynamics in both patterned and non-patterned ferromagnetic thin films, and emphasizes the significance of perpendicular magnetic anisotropyPerpendicular magnetic anisotropy (PMA) in this context as well. The chapter begins with an overview of the basic concept and relevance of spin wavesSpin wave (SW), followed by a detailed discussion of Brillouin light scatteringBrillouin light scattering (BLS) methodology. We explore the unique properties of spin wavesSpin wave (SW) in patterned films, such as magnonic crystalsMagnonic crystals (MC), and a comparative study with the behaviour in continuous films has been presented in detail. The future perspective from technological point of view of spin-wave research is vast, ranging from high-frequency data transmission to quantum information processing. Here we highlighted applications encompass spin-wave logic devices, magnonic waveguide, quantum computingSpin wave computing, and the role of spin wavesSpin wave (SW) in the development of novel materials with tailored magnetic properties. Finally, this review addresses the challenges associated with achieving precise control over spin-waveSpin wave (SW) propagation, elucidating spin-waveSpin wave (SW) interactions at the nanoscale, and integrating spin-waveSpin wave (SW) technology with existing technological frameworks.}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } Exploring spin-waveSpin wave (SW) dynamics opens new avenues for technological applications across various fields. This chapter provides a comprehensive review of spin-waveSpin wave (SW) dynamics in both patterned and non-patterned ferromagnetic thin films, and emphasizes the significance of perpendicular magnetic anisotropyPerpendicular magnetic anisotropy (PMA) in this context as well. The chapter begins with an overview of the basic concept and relevance of spin wavesSpin wave (SW), followed by a detailed discussion of Brillouin light scatteringBrillouin light scattering (BLS) methodology. We explore the unique properties of spin wavesSpin wave (SW) in patterned films, such as magnonic crystalsMagnonic crystals (MC), and a comparative study with the behaviour in continuous films has been presented in detail. The future perspective from technological point of view of spin-wave research is vast, ranging from high-frequency data transmission to quantum information processing. Here we highlighted applications encompass spin-wave logic devices, magnonic waveguide, quantum computingSpin wave computing, and the role of spin wavesSpin wave (SW) in the development of novel materials with tailored magnetic properties. Finally, this review addresses the challenges associated with achieving precise control over spin-waveSpin wave (SW) propagation, elucidating spin-waveSpin wave (SW) interactions at the nanoscale, and integrating spin-waveSpin wave (SW) technology with existing technological frameworks. |
| 281. | Marceli Kaczmarski, Jacek Jenczyk, Bogusław Mróz Phason and Amplitudon Modes in K3Na(SeO4)2 Crystal Symmetry, 16 (11), 2024, ISSN: 2073-8994. @article{sym16111482, title = {Phason and Amplitudon Modes in K3Na(SeO4)2 Crystal}, author = {Marceli Kaczmarski and Jacek Jenczyk and Bogusław Mróz}, url = {https://www.mdpi.com/2073-8994/16/11/1482}, doi = {10.3390/sym16111482}, issn = {2073-8994}, year = {2024}, date = {2024-11-06}, journal = {Symmetry}, volume = {16}, number = {11}, abstract = {For the first time, the Nambu–Goldstone optical mode has been observed in ferroelastic crystals. The amplitudon and phason modes were identified in the Raman spectra of the K3Na(SeO4)2 (KNSe) crystal. We discuss the occurrence of such lattice vibration with regard to the possible presence of an incommensurate (IC) phase. The potential scenario of the dynamics of the SO4 tetrahedron leading to the appearance of an IC phase, accompanied by critical temperature behavior of two external vibrations of Ag symmetry, is given together with the molecular mechanism of the phase transitions in the material studied. The effect of the spatial reorganization of the crystal lattice associated with the ferroelastic domains of the KNSe crystal of W and W′ types is also discussed. We show that the emergence of such a domain structure may also be a source of incommensurability.}, keywords = {}, pubstate = {published}, tppubtype = {article} } For the first time, the Nambu–Goldstone optical mode has been observed in ferroelastic crystals. The amplitudon and phason modes were identified in the Raman spectra of the K3Na(SeO4)2 (KNSe) crystal. We discuss the occurrence of such lattice vibration with regard to the possible presence of an incommensurate (IC) phase. The potential scenario of the dynamics of the SO4 tetrahedron leading to the appearance of an IC phase, accompanied by critical temperature behavior of two external vibrations of Ag symmetry, is given together with the molecular mechanism of the phase transitions in the material studied. The effect of the spatial reorganization of the crystal lattice associated with the ferroelastic domains of the KNSe crystal of W and W′ types is also discussed. We show that the emergence of such a domain structure may also be a source of incommensurability. |
| 280. | Anuj K Dhiman, Nikodem Leśniewski, Ryszard Gieniusz, Jan Kisielewski, Piotr Mazalski, Zbigniew Kurant, Michał Matczak, Feliks Stobiecki, Maciej Krawczyk, Artem Lynnyk, Andrzej Maziewski, Paweł Gruszecki APL Materials, 12 (11), pp. 111106, 2024, ISSN: 2166-532X. @article{10.1063/5.0227380, title = {Reconfigurable magnonic crystals: Spin wave propagation in Pt/Co multilayer in saturated and stripe domain phase}, author = {Anuj K Dhiman and Nikodem Leśniewski and Ryszard Gieniusz and Jan Kisielewski and Piotr Mazalski and Zbigniew Kurant and Michał Matczak and Feliks Stobiecki and Maciej Krawczyk and Artem Lynnyk and Andrzej Maziewski and Paweł Gruszecki}, url = {https://doi.org/10.1063/5.0227380}, doi = {10.1063/5.0227380}, issn = {2166-532X}, year = {2024}, date = {2024-11-04}, journal = {APL Materials}, volume = {12}, number = {11}, pages = {111106}, abstract = {To control the spin wave (SW) propagation, external energy sources such as magnetic fields, electric currents, or complex nanopatterning are used, which can be challenging at the deep nanoscale level. In this work, we overcome such limitations by demonstrating SW propagation in Pt/Co multilayers at a remanent state controlled by stripe domain patterns, using Brillouin light scattering and micromagnetic simulations. We show that parallel stripes with a periodicity around 100 nm exhibit reconfigurability, as the stripes can be rotated by applying the in-plane field without damaging their shape. This allows us to study SW propagation perpendicular and parallel to the stripes. We observe multimodal SW spectra—three bands in perpendicular and five in parallel geometry. Numerical results allow us to identify all observed modes and to explain the differences between two configurations by the unequal contribution of all three magnetization components in the SW dynamics. We find that the experimentally measured non-reciprocal dispersion (for the wavevector perpendicular to the stripes) is not the breaking of time-symmetry but the asymmetry in intensity of the measured signals of two different low-frequency modes, which is due to the inhomogeneous SW amplitude distribution over the multilayer thickness and the limited light penetration depth. Our results pave the way for easy reprogrammability and high energy efficiency in nanomagnonics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } To control the spin wave (SW) propagation, external energy sources such as magnetic fields, electric currents, or complex nanopatterning are used, which can be challenging at the deep nanoscale level. In this work, we overcome such limitations by demonstrating SW propagation in Pt/Co multilayers at a remanent state controlled by stripe domain patterns, using Brillouin light scattering and micromagnetic simulations. We show that parallel stripes with a periodicity around 100 nm exhibit reconfigurability, as the stripes can be rotated by applying the in-plane field without damaging their shape. This allows us to study SW propagation perpendicular and parallel to the stripes. We observe multimodal SW spectra—three bands in perpendicular and five in parallel geometry. Numerical results allow us to identify all observed modes and to explain the differences between two configurations by the unequal contribution of all three magnetization components in the SW dynamics. We find that the experimentally measured non-reciprocal dispersion (for the wavevector perpendicular to the stripes) is not the breaking of time-symmetry but the asymmetry in intensity of the measured signals of two different low-frequency modes, which is due to the inhomogeneous SW amplitude distribution over the multilayer thickness and the limited light penetration depth. Our results pave the way for easy reprogrammability and high energy efficiency in nanomagnonics. |
| 279. | Wanhua Su, Wei Qin, Adam Miranowicz, Tao Li, Franco Nori Heralded nonlocal quantum gates for distributed quantum computation in a decoherence-free subspace Phys. Rev. A, 110 , pp. 052612, 2024. @article{Su2024pra, title = {Heralded nonlocal quantum gates for distributed quantum computation in a decoherence-free subspace}, author = {Wanhua Su and Wei Qin and Adam Miranowicz and Tao Li and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevA.110.052612}, doi = {10.1103/PhysRevA.110.052612}, year = {2024}, date = {2024-11-01}, journal = {Phys. Rev. A}, volume = {110}, pages = {052612}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 278. | Julia Kharlan, Krzysztof Szulc, Jarosław W Kłos, Grzegorz Centała Tunable magnonic crystal in a hybrid superconductor-ferrimagnet nanostructure Scientific Reports, 14 (1), pp. 25594, 2024, ISSN: 2045-2322. @article{Kharlan2024, title = {Tunable magnonic crystal in a hybrid superconductor-ferrimagnet nanostructure}, author = {Julia Kharlan and Krzysztof Szulc and Jarosław W Kłos and Grzegorz Centała}, url = {https://doi.org/10.1038/s41598-024-75492-0}, doi = {10.1038/s41598-024-75492-0}, issn = {2045-2322}, year = {2024}, date = {2024-10-26}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {25594}, abstract = {One of the most intriguing properties of magnonic systems is their reconfigurability, where an external magnetic field alters the static magnetic configuration to influence magnetization dynamics. In this paper, we present an alternative approach to tunable magnonic systems. We studied theoretically and numerically a magnonic crystal induced within a uniform magnetic layer by a periodic magnetic field pattern created by the sequence of superconducting strips. We showed that the spin-wave spectrum can be tuned by the inhomogeneous stray field of the superconductor in response to a small uniform external magnetic field. Additionally, we demonstrated that modifying the width of superconducting strips and separation between them leads to the changes in the internal field which are unprecedented in conventional magnonic structures. The paper presents the results of semi-analytical calculations for realistic structures, which are verified by finite-element method computations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } One of the most intriguing properties of magnonic systems is their reconfigurability, where an external magnetic field alters the static magnetic configuration to influence magnetization dynamics. In this paper, we present an alternative approach to tunable magnonic systems. We studied theoretically and numerically a magnonic crystal induced within a uniform magnetic layer by a periodic magnetic field pattern created by the sequence of superconducting strips. We showed that the spin-wave spectrum can be tuned by the inhomogeneous stray field of the superconductor in response to a small uniform external magnetic field. Additionally, we demonstrated that modifying the width of superconducting strips and separation between them leads to the changes in the internal field which are unprecedented in conventional magnonic structures. The paper presents the results of semi-analytical calculations for realistic structures, which are verified by finite-element method computations. |
| 277. | Bivas Rana Journal of Applied Physics, 136 (15), pp. 150701, 2024, ISSN: 0021-8979. @article{10.1063/5.0233693, title = {Role of voltage-controlled magnetic anisotropy in the recent development of magnonics and spintronics}, author = {Bivas Rana}, url = {https://doi.org/10.1063/5.0233693}, doi = {10.1063/5.0233693}, issn = {0021-8979}, year = {2024}, date = {2024-10-16}, journal = {Journal of Applied Physics}, volume = {136}, number = {15}, pages = {150701}, abstract = {With significant recent progress in the thin film deposition and nanofabrication technology, a number of physical phenomena occur at the interfaces of magnetic thin films, and their heterostructures have been discovered. Consequently, the electric field-induced modulation of those interfacial properties mediated through spin–orbit coupling promises to develop magnetic material based smarter, faster, miniaturized, energy efficient spintronic devices. Among them, the electric field-induced modification of interfacial magnetic anisotropy, popularly termed as voltage-controlled magnetic anisotropy (VCMA), has attracted special attention because of its salient features. This article is devoted to reviewing the recent development of magnonics, which deals with collective precessional motion of ordered magnetic spins, i.e., spin waves (SWs), and skyrmions with chiral spin textures, with VCMA, including the perspectives of this research field. Starting with a broad introduction, the key features of VCMA and its advantages over other electric field-induced methods are highlighted. These are followed by describing the state-of-the-art of VCMA, and various other direct and indirect electric field-induced methods for magnetization reversal; controlling skyrmion dynamics; excitation, manipulation, and channeling of SWs; and tailoring magnonic bands. The critical challenges, their possible solutions, and future perspectives of this field are thoroughly discussed throughout the article.}, keywords = {}, pubstate = {published}, tppubtype = {article} } With significant recent progress in the thin film deposition and nanofabrication technology, a number of physical phenomena occur at the interfaces of magnetic thin films, and their heterostructures have been discovered. Consequently, the electric field-induced modulation of those interfacial properties mediated through spin–orbit coupling promises to develop magnetic material based smarter, faster, miniaturized, energy efficient spintronic devices. Among them, the electric field-induced modification of interfacial magnetic anisotropy, popularly termed as voltage-controlled magnetic anisotropy (VCMA), has attracted special attention because of its salient features. This article is devoted to reviewing the recent development of magnonics, which deals with collective precessional motion of ordered magnetic spins, i.e., spin waves (SWs), and skyrmions with chiral spin textures, with VCMA, including the perspectives of this research field. Starting with a broad introduction, the key features of VCMA and its advantages over other electric field-induced methods are highlighted. These are followed by describing the state-of-the-art of VCMA, and various other direct and indirect electric field-induced methods for magnetization reversal; controlling skyrmion dynamics; excitation, manipulation, and channeling of SWs; and tailoring magnonic bands. The critical challenges, their possible solutions, and future perspectives of this field are thoroughly discussed throughout the article. |
| 276. | Peter Zalom, Kacper Wrześniewski, Tomáš Novotný, Ireneusz Weymann Double quantum dot Andreev molecules: Phase diagrams and critical evaluation of effective models Physical Review B, 110 , pp. 134506, 2024. @article{Zalom2024, title = {Double quantum dot Andreev molecules: Phase diagrams and critical evaluation of effective models}, author = {Peter Zalom and Kacper Wrześniewski and Tomáš Novotný and Ireneusz Weymann}, url = {https://journals.aps.org/prb/abstract/10.1103/PhysRevB.110.134506}, doi = {10.1103/PhysRevB.110.134506}, year = {2024}, date = {2024-10-07}, journal = {Physical Review B}, volume = {110}, pages = {134506}, abstract = {This paper systematically investigates the phase diagram of a parallel double-quantum-dot Andreev molecule, where the two quantum dots are coupled to a common superconducting lead. Using the numerical renormalization group method, we map out the evolution of the ground state across a wide parameter space of level detunings, size of the superconducting gap, lead couplings, and interdot coupling strength. The intricate phase diagrams feature singlet, doublet, and a relatively uncommon triplet ground states, with the latter being a distinct signature of strong lead-mediated interactions between the quantum dots. We benchmark the applicability of simplified effective models, including the atomic limit and zero-bandwidth approximations, in capturing the complex behavior of this parallel configuration. Our analysis reveals severe limitations of these models, underscoring the necessity for maximal caution when extrapolating beyond their tested validity. In particular, all effective models except for the extended version of the zero-bandwidth approximation failed in reproducing the triplet ground state and made several false predictions. These findings provide crucial insights for interpreting experimental observations and designing superconducting devices based on quantum-dot architectures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This paper systematically investigates the phase diagram of a parallel double-quantum-dot Andreev molecule, where the two quantum dots are coupled to a common superconducting lead. Using the numerical renormalization group method, we map out the evolution of the ground state across a wide parameter space of level detunings, size of the superconducting gap, lead couplings, and interdot coupling strength. The intricate phase diagrams feature singlet, doublet, and a relatively uncommon triplet ground states, with the latter being a distinct signature of strong lead-mediated interactions between the quantum dots. We benchmark the applicability of simplified effective models, including the atomic limit and zero-bandwidth approximations, in capturing the complex behavior of this parallel configuration. Our analysis reveals severe limitations of these models, underscoring the necessity for maximal caution when extrapolating beyond their tested validity. In particular, all effective models except for the extended version of the zero-bandwidth approximation failed in reproducing the triplet ground state and made several false predictions. These findings provide crucial insights for interpreting experimental observations and designing superconducting devices based on quantum-dot architectures. |
| 275. | Piotr Graczyk, Maria Pugaczowa-Michalska, Maciej Krawczyk Generation of femtosecond spin-polarized current pulses at Fe/MgO interface by quasi-static voltage Physica E: Low-dimensional Systems and Nanostructures, 165 , pp. 116120, 2024, ISSN: 1386-9477. @article{GRACZYK2025116120, title = {Generation of femtosecond spin-polarized current pulses at Fe/MgO interface by quasi-static voltage}, author = {Piotr Graczyk and Maria Pugaczowa-Michalska and Maciej Krawczyk}, url = {https://www.sciencedirect.com/science/article/pii/S1386947724002248}, doi = {https://doi.org/10.1016/j.physe.2024.116120}, issn = {1386-9477}, year = {2024}, date = {2024-10-03}, journal = {Physica E: Low-dimensional Systems and Nanostructures}, volume = {165}, pages = {116120}, abstract = {The generation of short spin-current pulses is essential for fast spintronic devices. So far, spin current pulses are generated by femtosecond laser pulses which drive spins from a ferromagnetic metal layer. However, the need for miniaturization, simplicity and energy efficiency favour electric-field control of spintronic devices over optic or thermal control. Here, we combine ab initio calculations of electronic density of states at MgO/Fe interface with continuous model for charge transport to investigate the dynamics of the spin-dependent potential. We demonstrate that the voltage-driven instability of the electronic band structure due to the electronic resonant states at the Fe/MgO interface results in the generation of the femtosecond spin-polarized current pulse with the spin polarization up to P=7 00 % that propagates from the interface to the bulk. The dynamics of the current pulses driven by the Stoner instability depends neither on the dielectric relaxation time nor on the details of how the instability is achieved by changing the voltage, i.e. as long as the voltage changes are slow (quasi-static) with respect to the time determined by the spin diffusion constant, being of the order of fs. The presence of the instability can be detected by THz time-domain spectroscopy or pump-probe techniques.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The generation of short spin-current pulses is essential for fast spintronic devices. So far, spin current pulses are generated by femtosecond laser pulses which drive spins from a ferromagnetic metal layer. However, the need for miniaturization, simplicity and energy efficiency favour electric-field control of spintronic devices over optic or thermal control. Here, we combine ab initio calculations of electronic density of states at MgO/Fe interface with continuous model for charge transport to investigate the dynamics of the spin-dependent potential. We demonstrate that the voltage-driven instability of the electronic band structure due to the electronic resonant states at the Fe/MgO interface results in the generation of the femtosecond spin-polarized current pulse with the spin polarization up to P=7 00 % that propagates from the interface to the bulk. The dynamics of the current pulses driven by the Stoner instability depends neither on the dielectric relaxation time nor on the details of how the instability is achieved by changing the voltage, i.e. as long as the voltage changes are slow (quasi-static) with respect to the time determined by the spin diffusion constant, being of the order of fs. The presence of the instability can be detected by THz time-domain spectroscopy or pump-probe techniques. |
| 274. | Sławomir Mamica Scientific Reports, 14 (1), pp. 22966, 2024, ISSN: 2045-2322. @article{mamica_spin-wave_2024, title = {Spin-wave mode coupling in the presence of the demagnetizing field in cobalt-permalloy magnonic crystals}, author = {Sławomir Mamica}, url = {https://www.nature.com/articles/s41598-024-74923-2}, doi = {10.1038/s41598-024-74923-2}, issn = {2045-2322}, year = {2024}, date = {2024-10-03}, urldate = {2024-10-11}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {22966}, abstract = {We present the results of studies on the non-uniform frequency shift of spin wave spectrum in a two-dimensional magnonic crystal of cobalt/permalloy under the influence of external magnetic field changes. We investigate the phenomenon of coupling of modes and, as a consequence, their hybridization. By taking advantage of the fact that compressing the crystal structure along the direction of the external magnetic field leads to an enhancement of the demagnetizing field, we analyse its effect on the frequency shift of individual modes depending on their concentration in Co. We show that the consequence of this enhancement is a shift in the coupling of modes towards higher magnetic fields. This provides a potential opportunity to design which pairs of modes and in what range of fields hybridization will occur.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present the results of studies on the non-uniform frequency shift of spin wave spectrum in a two-dimensional magnonic crystal of cobalt/permalloy under the influence of external magnetic field changes. We investigate the phenomenon of coupling of modes and, as a consequence, their hybridization. By taking advantage of the fact that compressing the crystal structure along the direction of the external magnetic field leads to an enhancement of the demagnetizing field, we analyse its effect on the frequency shift of individual modes depending on their concentration in Co. We show that the consequence of this enhancement is a shift in the coupling of modes towards higher magnetic fields. This provides a potential opportunity to design which pairs of modes and in what range of fields hybridization will occur. |
| 273. | D Panda, K K Behera, S Madhur, Bivas Rana, A Gloskovskii, Y Otani, A Barman, I Sarkar Phys. Rev. B, 110 , pp. 094424, 2024. @article{PhysRevB.110.094424, title = {Role of the nonmagnetic underlayer in controlling the electronic structure of ferromagnet/nonmagnetic-metal heterostructures}, author = {D Panda and K K Behera and S Madhur and Bivas Rana and A Gloskovskii and Y Otani and A Barman and I Sarkar}, url = {https://link.aps.org/doi/10.1103/PhysRevB.110.094424}, doi = {10.1103/PhysRevB.110.094424}, year = {2024}, date = {2024-09-18}, journal = {Phys. Rev. B}, volume = {110}, pages = {094424}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 272. | Ievgen I Arkhipov, Fabrizio Minganti, Adam Miranowicz, Sahin K Özdemir, Franco Nori Restoring Adiabatic State Transfer in Time-Modulated Non-Hermitian Systems Phys. Rev. Lett., 133 , pp. 113802, 2024. @article{Arkhipov24prl, title = {Restoring Adiabatic State Transfer in Time-Modulated Non-Hermitian Systems}, author = {Ievgen I Arkhipov and Fabrizio Minganti and Adam Miranowicz and Sahin K Özdemir and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevLett.133.113802}, doi = {10.1103/PhysRevLett.133.113802}, year = {2024}, date = {2024-09-01}, journal = {Phys. Rev. Lett.}, volume = {133}, pages = {113802}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 271. | Shashank Shekhar, Sławomir Mielcarek, Y Otani, Bivas Rana, Aleksandra Trzaskowska Effect of the underlayer on the elastic parameters of the CoFeB/MgO heterostructures Scientific Reports, 14 (1), pp. 20259, 2024, ISSN: 2045-2322. @article{shekhar_effect_2024, title = {Effect of the underlayer on the elastic parameters of the CoFeB/MgO heterostructures}, author = {Shashank Shekhar and Sławomir Mielcarek and Y Otani and Bivas Rana and Aleksandra Trzaskowska}, url = {https://www.nature.com/articles/s41598-024-71110-1}, doi = {10.1038/s41598-024-71110-1}, issn = {2045-2322}, year = {2024}, date = {2024-08-31}, urldate = {2024-09-12}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {20259}, abstract = {We investigated the thermally induced surface acoustic waves in CoFeB/MgO heterostructures with different underlayer materials. Our results show a direct correlation between the density and elastic parameters of the underlayer materials and the surface phonon dispersion. Using finite element method-based simulations, we calculate the effective elastic parameters (such as elastic tensor, Young’s modulus, and Poisson’s ratio) for multilayers with different underlayer materials. The simulation results, either considering the elastic parameters of individual layers or considering the effective elastic parameters of whole stacks, exhibit good agreement with the experimental data. This study will help us deepen our understanding of phonon properties and their interactions with other quasiparticles or magnetic textures with the help of these estimated elastic properties.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigated the thermally induced surface acoustic waves in CoFeB/MgO heterostructures with different underlayer materials. Our results show a direct correlation between the density and elastic parameters of the underlayer materials and the surface phonon dispersion. Using finite element method-based simulations, we calculate the effective elastic parameters (such as elastic tensor, Young’s modulus, and Poisson’s ratio) for multilayers with different underlayer materials. The simulation results, either considering the elastic parameters of individual layers or considering the effective elastic parameters of whole stacks, exhibit good agreement with the experimental data. This study will help us deepen our understanding of phonon properties and their interactions with other quasiparticles or magnetic textures with the help of these estimated elastic properties. |
| 270. | Josef Kadlec, Karol Bartkiewicz, Antonín Černoch, Karel Lemr, Adam Miranowicz Experimental relative entanglement potentials of single-photon states Phys. Rev. A, 110 , pp. 023720, 2024. @article{PhysRevA.110.023720, title = {Experimental relative entanglement potentials of single-photon states}, author = {Josef Kadlec and Karol Bartkiewicz and Antonín Černoch and Karel Lemr and Adam Miranowicz}, url = {https://link.aps.org/doi/10.1103/PhysRevA.110.023720}, doi = {10.1103/PhysRevA.110.023720}, year = {2024}, date = {2024-08-01}, journal = {Phys. Rev. A}, volume = {110}, pages = {023720}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 269. | Riya Mehta, Bivas Rana, Susmita Saha Magnetization dynamics in quasiperiodic magnonic crystals Journal of Physics: Condensed Matter, 36 (44), pp. 443003, 2024. @article{Mehta_2024, title = {Magnetization dynamics in quasiperiodic magnonic crystals}, author = {Riya Mehta and Bivas Rana and Susmita Saha}, url = {https://dx.doi.org/10.1088/1361-648X/ad5ee8}, doi = {10.1088/1361-648X/ad5ee8}, year = {2024}, date = {2024-08-01}, journal = {Journal of Physics: Condensed Matter}, volume = {36}, number = {44}, pages = {443003}, publisher = {IOP Publishing}, abstract = {Quasiperiodic magnonic crystals, in contrast to their periodic counterparts, lack strict periodicity which gives rise to complex and localised spin wave spectra characterized by numerous band gaps and fractal features. Despite their intrinsic structural complexity, quasiperiodic nature of these magnonic crystals enables better tunability of spin wave spectra over their periodic counterparts and therefore holds promise for the applications in reprogrammable magnonic devices. In this article, we provide an overview of magnetization reversal and precessional magnetization dynamics studied so far in various quasiperiodic magnonic crystals, illustrating how their quasiperiodic nature gives rise to tailored band structure, enabling unparalleled control over spin waves. The review is concluded by highlighting the possible potential applications of these quasiperiodic magnonic crystals, exploring potential avenues for future exploration followed by a brief summary.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Quasiperiodic magnonic crystals, in contrast to their periodic counterparts, lack strict periodicity which gives rise to complex and localised spin wave spectra characterized by numerous band gaps and fractal features. Despite their intrinsic structural complexity, quasiperiodic nature of these magnonic crystals enables better tunability of spin wave spectra over their periodic counterparts and therefore holds promise for the applications in reprogrammable magnonic devices. In this article, we provide an overview of magnetization reversal and precessional magnetization dynamics studied so far in various quasiperiodic magnonic crystals, illustrating how their quasiperiodic nature gives rise to tailored band structure, enabling unparalleled control over spin waves. The review is concluded by highlighting the possible potential applications of these quasiperiodic magnonic crystals, exploring potential avenues for future exploration followed by a brief summary. |
| 268. | Piotr Majek, Ireneusz Weymann Spin-selective transport in a correlated double quantum dot-Majorana wire system Scientific Reports, 14 , pp. 17762, 2024. @article{Majek2024b, title = {Spin-selective transport in a correlated double quantum dot-Majorana wire system}, author = {Piotr Majek and Ireneusz Weymann}, url = {https://www.nature.com/articles/s41598-024-66478-z}, doi = {10.1038/s41598-024-66478-z}, year = {2024}, date = {2024-08-01}, journal = {Scientific Reports}, volume = {14}, pages = {17762}, abstract = {In this work we investigate the spin-dependent transport through a double quantum dot embedded in a ferromagnetic tunnel junction and side attached to a topological superconducting nanowire hosting Majorana zero-energy modes. We focus on the transport regime when the Majorana mode leaks into the double quantum dot competing with the two-stage Kondo effect and the ferromagnetic-contact-induced exchange field. In particular, we determine the system’s spectral properties and analyze the temperature dependence of the spin-resolved linear conductance by means of the numerical renormalization group method. Our study reveals unique signatures of the interplay between the spin-resolved tunneling, the Kondo effect and the Majorana modes, which are visible in the transport characteristics. In particular, we uncover a competing character of the coupling to topological superconductor and that to ferromagnetic leads, which can be observed already for very low spin polarization of the electrodes. This is signaled by an almost complete quenching of the conductance in one of the spin channels which is revealed through perfect conductance spin polarization. Moreover, we show that the conductance spin polarization can change sign depending on the magnitude of spin imbalance in the leads and strength of interaction with topological wire. Thus, our work demonstrates that even minuscule spin polarization of tunneling processes can have large impact on the transport properties of the system.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In this work we investigate the spin-dependent transport through a double quantum dot embedded in a ferromagnetic tunnel junction and side attached to a topological superconducting nanowire hosting Majorana zero-energy modes. We focus on the transport regime when the Majorana mode leaks into the double quantum dot competing with the two-stage Kondo effect and the ferromagnetic-contact-induced exchange field. In particular, we determine the system’s spectral properties and analyze the temperature dependence of the spin-resolved linear conductance by means of the numerical renormalization group method. Our study reveals unique signatures of the interplay between the spin-resolved tunneling, the Kondo effect and the Majorana modes, which are visible in the transport characteristics. In particular, we uncover a competing character of the coupling to topological superconductor and that to ferromagnetic leads, which can be observed already for very low spin polarization of the electrodes. This is signaled by an almost complete quenching of the conductance in one of the spin channels which is revealed through perfect conductance spin polarization. Moreover, we show that the conductance spin polarization can change sign depending on the magnitude of spin imbalance in the leads and strength of interaction with topological wire. Thus, our work demonstrates that even minuscule spin polarization of tunneling processes can have large impact on the transport properties of the system. |
| 267. | Aleksey Girich, Liubov Ivzhenko, Ganna Kharchenko, Sergey Polevoy, Sergey Tarapov, Maciej Krawczyk, Jarosław W. Kłos Existence of edge modes in periodic microstrip transmission line Scientific Reports, 14 (1), pp. 16477, 2024, ISSN: 2045-2322. @article{girich_existence_2024, title = {Existence of edge modes in periodic microstrip transmission line}, author = {Aleksey Girich and Liubov Ivzhenko and Ganna Kharchenko and Sergey Polevoy and Sergey Tarapov and Maciej Krawczyk and Jarosław W. Kłos}, url = {https://www.nature.com/articles/s41598-024-67610-9}, doi = {10.1038/s41598-024-67610-9}, issn = {2045-2322}, year = {2024}, date = {2024-07-16}, urldate = {2024-07-17}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {16477}, abstract = {The microstrip of modulated width is a realization of a one-dimensional photonic crystal operating in the microwave regime. Like any photonic crystal, the periodic microstrip is characterised by the presence of frequency bands and band gaps that enable and prohibit wave propagation, respectively. The frequency bands for microstrip of the symmetric unit cell can be distinguished by 0 or pi Zak phase. The sum of these topological parameters for all bands below a given frequency gap determines the value of the surface impedance at the end of the microstrip. We demonstrate that edge modes are absent in a finite microstrip terminated at both ends in the centres of unit cells, but they can be induced by adding the defected cells. Edge modes present at both ends of the microstrip enable microwave tunneling with high transitivity in the frequency gap with or without a change in phase. This has been demonstrated experimentally and developed in detail using numerical simulations and model calculations. The investigated system, with a doublet of edge modes in the frequency gap, can be considered as a narrow passband filter of high selectivity and characterised by a significant group delay.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The microstrip of modulated width is a realization of a one-dimensional photonic crystal operating in the microwave regime. Like any photonic crystal, the periodic microstrip is characterised by the presence of frequency bands and band gaps that enable and prohibit wave propagation, respectively. The frequency bands for microstrip of the symmetric unit cell can be distinguished by 0 or pi Zak phase. The sum of these topological parameters for all bands below a given frequency gap determines the value of the surface impedance at the end of the microstrip. We demonstrate that edge modes are absent in a finite microstrip terminated at both ends in the centres of unit cells, but they can be induced by adding the defected cells. Edge modes present at both ends of the microstrip enable microwave tunneling with high transitivity in the frequency gap with or without a change in phase. This has been demonstrated experimentally and developed in detail using numerical simulations and model calculations. The investigated system, with a doublet of edge modes in the frequency gap, can be considered as a narrow passband filter of high selectivity and characterised by a significant group delay. |
| 266. | Ryszard Taranko, Kacper Wrześniewski, Ireneusz Weymann, Tadeusz Domański Transient effects in quantum dots contacted via topological superconductor Physical Review B, 110 , pp. 035413, 2024. @article{Taranko2024, title = {Transient effects in quantum dots contacted via topological superconductor}, author = {Ryszard Taranko and Kacper Wrześniewski and Ireneusz Weymann and Tadeusz Domański}, url = {https://journals.aps.org/prb/abstract/10.1103/PhysRevB.110.035413}, doi = {10.1103/PhysRevB.110.035413}, year = {2024}, date = {2024-07-10}, journal = {Physical Review B}, volume = {110}, pages = {035413}, abstract = {We investigate gradual development of the quasiparticle states in two quantum dots attached to opposite sides of the topological superconducting nanowire, hosting the boundary modes. Specifically, we explore the nonequilibrium cross-correlations transmitted between these quantum dots via the zero-energy Majorana modes. Our analytical and numerical results reveal the nonlocal features observable in the transient behavior of electron pairing, which subsequently cease while the hybrid structure evolves towards its asymptotic steady-state configuration. We estimate duration of these temporary phenomena. Using the nonperturbative scheme of the time-dependent numerical renormalization group technique we also analyze nonequilibrium signatures of the correlation effects competing with the proximity induced electron pairing. These dynamical processes could manifest themselves in braiding protocols imposed on the topological and/or conventional superconducting quantum bits, using superconducting hybrid nanostructures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigate gradual development of the quasiparticle states in two quantum dots attached to opposite sides of the topological superconducting nanowire, hosting the boundary modes. Specifically, we explore the nonequilibrium cross-correlations transmitted between these quantum dots via the zero-energy Majorana modes. Our analytical and numerical results reveal the nonlocal features observable in the transient behavior of electron pairing, which subsequently cease while the hybrid structure evolves towards its asymptotic steady-state configuration. We estimate duration of these temporary phenomena. Using the nonperturbative scheme of the time-dependent numerical renormalization group technique we also analyze nonequilibrium signatures of the correlation effects competing with the proximity induced electron pairing. These dynamical processes could manifest themselves in braiding protocols imposed on the topological and/or conventional superconducting quantum bits, using superconducting hybrid nanostructures. |
| 265. | Vojtiěch Trávníček, Jan Roik, Karol Bartkiewicz, Antonín Černoch, Paweł Horodecki, Karel Lemr Sensitivity versus selectivity in entanglement detection via collective witnesses Phys. Rev. Res., 6 , pp. 033056, 2024. @article{PhysRevResearch.6.033056, title = {Sensitivity versus selectivity in entanglement detection via collective witnesses}, author = {Vojtiěch Trávníček and Jan Roik and Karol Bartkiewicz and Antonín Černoch and Paweł Horodecki and Karel Lemr}, url = {https://link.aps.org/doi/10.1103/PhysRevResearch.6.033056}, doi = {10.1103/PhysRevResearch.6.033056}, year = {2024}, date = {2024-07-01}, journal = {Phys. Rev. Res.}, volume = {6}, pages = {033056}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 264. | Anna Jelec, Karol Bartkiewicz, Katarzyna Stachowiak-Szymczak, Joanna Ziobro-Strzępek Why not(es)? Automatic analysis of notes for consecutive interpreting training Biernacka Agnieszka, Figiel Wojciech (Ed.): 18 (12), pp. 245-268, Peter Lang Verlag, Berlin, Bruxelles, Chennai, Lausanne, New York, Oxford, 2024, ISBN: 9783631907122. @inbook{UAM3e12f04642694835a7c486a6658d9b64, title = {Why not(es)? Automatic analysis of notes for consecutive interpreting training}, author = {Anna Jelec and Karol Bartkiewicz and Katarzyna Stachowiak-Szymczak and Joanna Ziobro-Strzępek}, editor = {Biernacka Agnieszka, Figiel Wojciech}, url = {https://www.peterlang.com/document/1370692}, doi = {10.3726/b21104}, isbn = {9783631907122}, year = {2024}, date = {2024-07-01}, journal = {Phys. Rev. Res.}, volume = {18}, number = {12}, pages = {245-268}, publisher = {Peter Lang Verlag}, address = {Berlin, Bruxelles, Chennai, Lausanne, New York, Oxford}, series = {Studies in Language, Culture and Society: New Insights into Interpreting Studies}, abstract = {This volume is a collective work of eighteen eminent researchers representing various sub-fields of Interpreting Studies who contribute with fourteen chapters. The topics include various areas and approaches: interpreting from a philosophical, sociological and historical perspective, ethics of interpreters, court interpreting, public service interpreting, signed language interpreting, interpreting for minors and for refugees and asylum seekers, note-taking in consecutive interpreting, accessibility, as well as technology in interpreting and interpreter training. The multiplicity of themes and the multifaceted nature of the research prove that Interpreting Studies is nowadays a field that combines different disciplines and methodologies.}, type = {book}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } This volume is a collective work of eighteen eminent researchers representing various sub-fields of Interpreting Studies who contribute with fourteen chapters. The topics include various areas and approaches: interpreting from a philosophical, sociological and historical perspective, ethics of interpreters, court interpreting, public service interpreting, signed language interpreting, interpreting for minors and for refugees and asylum seekers, note-taking in consecutive interpreting, accessibility, as well as technology in interpreting and interpreter training. The multiplicity of themes and the multifaceted nature of the research prove that Interpreting Studies is nowadays a field that combines different disciplines and methodologies. |
| 263. | Anna Krzyżewska, Anna Dyrdał Phys. Status Solidi RRL, 2024, ISSN: 1862-6254. @article{Krzyzewska2024Jun, title = {Nonlinear Hall Effect in Isotropic k-Cubed Rashba Model: Berry-Curvature-Dipole Engineering by In-Plane Magnetic Field}, author = {Anna Krzyżewska and Anna Dyrdał}, url = {https://onlinelibrary.wiley.com/doi/10.1002/pssr.202400123 https://arxiv.org/abs/2404.07352}, doi = {10.1002/pssr.202400123}, issn = {1862-6254}, year = {2024}, date = {2024-06-25}, journal = {Phys. Status Solidi RRL}, abstract = {The linear and nonlinear Hall effects in 2D electron gas are considered theoretically within the isotropic k-cubed Rashba model. It is shown that the presence of an out-of-plane external magnetic field or net magnetization is a necessary condition to induce a nonzero Berry curvature in the system, whereas an in-plane magnetic field tunes the Berry curvature leading to the Berry curvature dipole. Interestingly, in the linear response regime, the conductivity is dominated by the intrinsic component (Berry curvature component), whereas the second-order correction to the Hall current (i.e., the conductivity proportional to the external electric field) is dominated by the component independent of the Berry curvature dipole.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The linear and nonlinear Hall effects in 2D electron gas are considered theoretically within the isotropic k-cubed Rashba model. It is shown that the presence of an out-of-plane external magnetic field or net magnetization is a necessary condition to induce a nonzero Berry curvature in the system, whereas an in-plane magnetic field tunes the Berry curvature leading to the Berry curvature dipole. Interestingly, in the linear response regime, the conductivity is dominated by the intrinsic component (Berry curvature component), whereas the second-order correction to the Hall current (i.e., the conductivity proportional to the external electric field) is dominated by the component independent of the Berry curvature dipole. |
| 262. | Miłosz Zdunek, Shashank Shekhar, Sławomir Mielcarek, Aleksandra Trzaskowska Investigation of phonons and magnons in [Ni80Fe20/Au/Co/Au]N multilayers Journal of Physics: Condensed Matter, 36 (37), pp. 375801, 2024. @article{Zdunek_2024, title = {Investigation of phonons and magnons in [Ni80Fe20/Au/Co/Au]N multilayers}, author = {Miłosz Zdunek and Shashank Shekhar and Sławomir Mielcarek and Aleksandra Trzaskowska}, url = {https://dx.doi.org/10.1088/1361-648X/ad5486}, doi = {10.1088/1361-648X/ad5486}, year = {2024}, date = {2024-06-18}, journal = {Journal of Physics: Condensed Matter}, volume = {36}, number = {37}, pages = {375801}, publisher = {IOP Publishing}, abstract = {The interaction between phonons and magnons is a rapidly developing area of research, particularly in the field of acoustic spintronics. To discuss this interaction, it is necessary to observe two different waves (acoustic and spin waves) with the same frequency and wavelength. In the Ni80Fe20/Au/Co/Au system deposited on a silicon substrate, we observe the interaction between spin waves and surface acoustic waves using Brillouin light scattering spectroscopy. As a result, we can selectively control (activate or deactivate) the magnetoelastic interaction between the fundamental spin wave mode and surface acoustic waves. This is achieved by adjusting the magnetostrictive layer thickness in the multilayer. We demonstrate that by adjusting the number of layers in a multilayer structure, it is possible to precisely control the dispersion of surface acoustic waves while having minimal impact on the fundamental spin wave mode.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The interaction between phonons and magnons is a rapidly developing area of research, particularly in the field of acoustic spintronics. To discuss this interaction, it is necessary to observe two different waves (acoustic and spin waves) with the same frequency and wavelength. In the Ni80Fe20/Au/Co/Au system deposited on a silicon substrate, we observe the interaction between spin waves and surface acoustic waves using Brillouin light scattering spectroscopy. As a result, we can selectively control (activate or deactivate) the magnetoelastic interaction between the fundamental spin wave mode and surface acoustic waves. This is achieved by adjusting the magnetostrictive layer thickness in the multilayer. We demonstrate that by adjusting the number of layers in a multilayer structure, it is possible to precisely control the dispersion of surface acoustic waves while having minimal impact on the fundamental spin wave mode. |
| 261. | Grzegorz Górski, Krzysztof Paweł Wójcik, Jan Barański, Ireneusz Weymann, Tadeusz Domański Nonlocal correlations transmitted between quantum dots via short topological superconductor Scientific Reports, 13 , pp. 13848, 2024. @article{Górski2024, title = {Nonlocal correlations transmitted between quantum dots via short topological superconductor}, author = {Grzegorz Górski and Krzysztof Paweł Wójcik and Jan Barański and Ireneusz Weymann and Tadeusz Domański }, url = {https://www.nature.com/articles/s41598-024-64578-4}, doi = {10.1038/s41598-024-64578-4}, year = {2024}, date = {2024-06-15}, journal = {Scientific Reports}, volume = {13}, pages = {13848}, abstract = {We study the quasiparticle states and nonlocal correlations of a hybrid structure, comprising two quantum dots interconnected through a short-length topological superconducting nanowire hosting overlaping Majorana modes. We show that the hybridization between different components of this setup gives rise to the emergence of molecular states, which are responsible for nonlocal correlations. We inspect the resulting energy structure, focusing on the inter-dependence between the quasiparticles of individual quantum dots. We predict the existence of nonlocal effects, which could be accessed and probed by crossed Andreev reflection spectroscopy. Our study would be relevant to a recent experimental realization of the minimal Kitaev model [T. Dvir et al., Nature 614, 445 (2023)], by considering its hybrid structure with side-attached quantum dots.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We study the quasiparticle states and nonlocal correlations of a hybrid structure, comprising two quantum dots interconnected through a short-length topological superconducting nanowire hosting overlaping Majorana modes. We show that the hybridization between different components of this setup gives rise to the emergence of molecular states, which are responsible for nonlocal correlations. We inspect the resulting energy structure, focusing on the inter-dependence between the quasiparticles of individual quantum dots. We predict the existence of nonlocal effects, which could be accessed and probed by crossed Andreev reflection spectroscopy. Our study would be relevant to a recent experimental realization of the minimal Kitaev model [T. Dvir et al., Nature 614, 445 (2023)], by considering its hybrid structure with side-attached quantum dots. |
| 260. | Benedetta Flebus, Dirk Grundler, Bivas Rana, YoshiChika Otani, Igor Barsukov, Anjan Barman, Gianluca Gubbiotti, Pedro Landeros, Johan Akerman, Ursula Ebels, Philipp Pirro, Vladislav E Demidov, Katrin Schultheiss, Gyorgy Csaba, Qi Wang, Florin Ciubotaru, Dmitri E Nikonov, Ping Che, Riccardo Hertel, Teruo Ono, Dmytro Afanasiev, Johan Mentink, Theo Rasing, Burkard Hillebrands, Silvia Viola Kusminskiy, Wei Zhang, Chunhui Rita Du, Aurore Finco, Toeno van der Sar, Yunqiu Kelly Luo, Yoichi Shiota, Joseph Sklenar, Tao Yu, Jinwei Rao Journal of Physics: Condensed Matter, 36 (36), pp. 363501, 2024. @article{Flebus_2024, title = {The 2024 magnonics roadmap}, author = {Benedetta Flebus and Dirk Grundler and Bivas Rana and YoshiChika Otani and Igor Barsukov and Anjan Barman and Gianluca Gubbiotti and Pedro Landeros and Johan Akerman and Ursula Ebels and Philipp Pirro and Vladislav E Demidov and Katrin Schultheiss and Gyorgy Csaba and Qi Wang and Florin Ciubotaru and Dmitri E Nikonov and Ping Che and Riccardo Hertel and Teruo Ono and Dmytro Afanasiev and Johan Mentink and Theo Rasing and Burkard Hillebrands and Silvia Viola Kusminskiy and Wei Zhang and Chunhui Rita Du and Aurore Finco and Toeno van der Sar and Yunqiu Kelly Luo and Yoichi Shiota and Joseph Sklenar and Tao Yu and Jinwei Rao}, url = {`}, doi = {10.1088/1361-648X/ad399c}, year = {2024}, date = {2024-06-14}, journal = {Journal of Physics: Condensed Matter}, volume = {36}, number = {36}, pages = {363501}, publisher = {IOP Publishing}, abstract = {Magnonics is a research field that has gained an increasing interest in both the fundamental and applied sciences in recent years. This field aims to explore and functionalize collective spin excitations in magnetically ordered materials for modern information technologies, sensing applications and advanced computational schemes. Spin waves, also known as magnons, carry spin angular momenta that allow for the transmission, storage and processing of information without moving charges. In integrated circuits, magnons enable on-chip data processing at ultrahigh frequencies without the Joule heating, which currently limits clock frequencies in conventional data processors to a few GHz. Recent developments in the field indicate that functional magnonic building blocks for in-memory computation, neural networks and Ising machines are within reach. At the same time, the miniaturization of magnonic circuits advances continuously as the synergy of materials science, electrical engineering and nanotechnology allows for novel on-chip excitation and detection schemes. Such circuits can already enable magnon wavelengths of 50 nm at microwave frequencies in a 5G frequency band. Research into non-charge-based technologies is urgently needed in view of the rapid growth of machine learning and artificial intelligence applications, which consume substantial energy when implemented on conventional data processing units. In its first part, the 2024 Magnonics Roadmap provides an update on the recent developments and achievements in the field of nano-magnonics while defining its future avenues and challenges. In its second part, the Roadmap addresses the rapidly growing research endeavors on hybrid structures and magnonics-enabled quantum engineering. We anticipate that these directions will continue to attract researchers to the field and, in addition to showcasing intriguing science, will enable unprecedented functionalities that enhance the efficiency of alternative information technologies and computational schemes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Magnonics is a research field that has gained an increasing interest in both the fundamental and applied sciences in recent years. This field aims to explore and functionalize collective spin excitations in magnetically ordered materials for modern information technologies, sensing applications and advanced computational schemes. Spin waves, also known as magnons, carry spin angular momenta that allow for the transmission, storage and processing of information without moving charges. In integrated circuits, magnons enable on-chip data processing at ultrahigh frequencies without the Joule heating, which currently limits clock frequencies in conventional data processors to a few GHz. Recent developments in the field indicate that functional magnonic building blocks for in-memory computation, neural networks and Ising machines are within reach. At the same time, the miniaturization of magnonic circuits advances continuously as the synergy of materials science, electrical engineering and nanotechnology allows for novel on-chip excitation and detection schemes. Such circuits can already enable magnon wavelengths of 50 nm at microwave frequencies in a 5G frequency band. Research into non-charge-based technologies is urgently needed in view of the rapid growth of machine learning and artificial intelligence applications, which consume substantial energy when implemented on conventional data processing units. In its first part, the 2024 Magnonics Roadmap provides an update on the recent developments and achievements in the field of nano-magnonics while defining its future avenues and challenges. In its second part, the Roadmap addresses the rapidly growing research endeavors on hybrid structures and magnonics-enabled quantum engineering. We anticipate that these directions will continue to attract researchers to the field and, in addition to showcasing intriguing science, will enable unprecedented functionalities that enhance the efficiency of alternative information technologies and computational schemes. |
| 259. | Mutlu Gokkavas, T. F. Gundogdu, Ekmel Ozbay, Andriy E. Serebryannikov Scientific Reports, 14 (1), pp. 13636, 2024, ISSN: 2045-2322. @article{gokkavas_few-layer_2024, title = {Few-layer bifunctional metasurfaces enabling asymmetric and symmetric polarization-plane rotation at the subwavelength scale}, author = {Mutlu Gokkavas and T. F. Gundogdu and Ekmel Ozbay and Andriy E. Serebryannikov}, url = {https://www.nature.com/articles/s41598-024-62073-4}, doi = {10.1038/s41598-024-62073-4}, issn = {2045-2322}, year = {2024}, date = {2024-06-13}, urldate = {2024-06-13}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {13636}, abstract = {We introduce and numerically validate the concept of few-layer bifunctional metasurfaces comprising two arrays of quasiplanar subwavelength resonators and a middle grid (array of rectangular holes) that offer both symmetric and asymmetric transmissions connected, respectively, with symmetric and asymmetric polarization-plane rotation functionalities. The proposed structures are thinner than $$textbackslashlambda /7$$and free of diffractions. Usually, the structure’s symmetry or asymmetry, i.e. unbroken or broken spatial inversion symmetries, are considered for metasurfaces as prerequisites of the capability of symmetric or asymmetric conversion of linearly polarized waves, respectively. Due to the achieved adjustment of the resonances enabling the rotation of the polarization plane simultaneously for both orthogonal polarizations of the incident wave, the symmetric polarization-plane rotation functionality can be obtained within one subwavelength band, whereas the asymmetric polarization-plane rotation functionality associated with the asymmetric transmission is obtained within another subwavelength band. This combination of the functionalities in one subdiffraction structure is possible due to the optimal choice of the grid parameters, since they may strongly affect the coupling between the two resonator arrays. Although normal incidence is required for the targeted bifunctionality, the variations of the incidence angle can also be exploited for the enrichment of the overall functional capability. Variations of the polarization angle give another important degree of freedom. The connection between the polarization-angle dependence of cross-polarized transmission and capability of symmetric and asymmetric polarization-plane rotation functionalities is highlighted. The feasible designs of the bifunctional metasurfaces are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We introduce and numerically validate the concept of few-layer bifunctional metasurfaces comprising two arrays of quasiplanar subwavelength resonators and a middle grid (array of rectangular holes) that offer both symmetric and asymmetric transmissions connected, respectively, with symmetric and asymmetric polarization-plane rotation functionalities. The proposed structures are thinner than $$textbackslashlambda /7$$and free of diffractions. Usually, the structure’s symmetry or asymmetry, i.e. unbroken or broken spatial inversion symmetries, are considered for metasurfaces as prerequisites of the capability of symmetric or asymmetric conversion of linearly polarized waves, respectively. Due to the achieved adjustment of the resonances enabling the rotation of the polarization plane simultaneously for both orthogonal polarizations of the incident wave, the symmetric polarization-plane rotation functionality can be obtained within one subwavelength band, whereas the asymmetric polarization-plane rotation functionality associated with the asymmetric transmission is obtained within another subwavelength band. This combination of the functionalities in one subdiffraction structure is possible due to the optimal choice of the grid parameters, since they may strongly affect the coupling between the two resonator arrays. Although normal incidence is required for the targeted bifunctionality, the variations of the incidence angle can also be exploited for the enrichment of the overall functional capability. Variations of the polarization angle give another important degree of freedom. The connection between the polarization-angle dependence of cross-polarized transmission and capability of symmetric and asymmetric polarization-plane rotation functionalities is highlighted. The feasible designs of the bifunctional metasurfaces are discussed. |
| 258. | Julia Kharlan, Krzysztof Sobucki, Krzysztof Szulc, Sara Memarzadeh, Jarosław W. Kłos Spin-wave confinement in a hybrid superconductor-ferrimagnet nanostructure Phys. Rev. Appl., 21 , pp. 064007, 2024. @article{PhysRevApplied.21.064007, title = {Spin-wave confinement in a hybrid superconductor-ferrimagnet nanostructure}, author = {Julia Kharlan and Krzysztof Sobucki and Krzysztof Szulc and Sara Memarzadeh and Jarosław W. Kłos}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.21.064007}, doi = {10.1103/PhysRevApplied.21.064007}, year = {2024}, date = {2024-06-05}, journal = {Phys. Rev. Appl.}, volume = {21}, pages = {064007}, publisher = {American Physical Society}, abstract = {Eddy currents in a superconductor shield the magnetic field in its interior and are responsible for the formation of a magnetic stray field outside of the superconducting structure. The stray field can be controlled by the external magnetic field and affect the magnetization dynamics in the magnetic system placed in its range. In the case of a hybrid system consisting of a superconducting strip placed over a magnetic layer, we theoretically predict the confinement of spin waves in the well of the static stray field. The number of bound states and their frequencies can be controlled by an external magnetic field. We present the results of semianalytical calculations complemented by numerical modeling.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Eddy currents in a superconductor shield the magnetic field in its interior and are responsible for the formation of a magnetic stray field outside of the superconducting structure. The stray field can be controlled by the external magnetic field and affect the magnetization dynamics in the magnetic system placed in its range. In the case of a hybrid system consisting of a superconducting strip placed over a magnetic layer, we theoretically predict the confinement of spin waves in the well of the static stray field. The number of bound states and their frequencies can be controlled by an external magnetic field. We present the results of semianalytical calculations complemented by numerical modeling. |
| 257. | Yunlan Zuo, Ya-Feng Jiao, Xun-Wei Xu, Adam Miranowicz, Le-Man Kuang, Hui Jing Chiral photon blockade in the spinning Kerr resonator Opt. Express, 32 (12), pp. 22020–22030, 2024. @article{Zuo2024, title = {Chiral photon blockade in the spinning Kerr resonator}, author = {Yunlan Zuo and Ya-Feng Jiao and Xun-Wei Xu and Adam Miranowicz and Le-Man Kuang and Hui Jing}, url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-32-12-22020}, doi = {10.1364/OE.524680}, year = {2024}, date = {2024-06-01}, journal = {Opt. Express}, volume = {32}, number = {12}, pages = {22020--22030}, publisher = {Optica Publishing Group}, abstract = {We propose how to achieve chiral photon blockade by spinning a nonlinear optical resonator. We show that by driving such a device at a fixed direction, completely different quantum effects can emerge for the counter-propagating optical modes, due to the spinning-induced breaking of time-reversal symmetry, which otherwise is unattainable for the same device in the static regime. Also, we find that in comparison with the static case, robust non-classical correlations against random backscattering losses can be achieved for such a quantum chiral system. Our work, extending previous works on the spontaneous breaking of optical chiral symmetry from the classical to purely quantum regimes, can stimulate more efforts towards making and utilizing various chiral quantum effects, including applications for chiral quantum networks or noise-tolerant quantum sensors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose how to achieve chiral photon blockade by spinning a nonlinear optical resonator. We show that by driving such a device at a fixed direction, completely different quantum effects can emerge for the counter-propagating optical modes, due to the spinning-induced breaking of time-reversal symmetry, which otherwise is unattainable for the same device in the static regime. Also, we find that in comparison with the static case, robust non-classical correlations against random backscattering losses can be achieved for such a quantum chiral system. Our work, extending previous works on the spontaneous breaking of optical chiral symmetry from the classical to purely quantum regimes, can stimulate more efforts towards making and utilizing various chiral quantum effects, including applications for chiral quantum networks or noise-tolerant quantum sensors. |
| 256. | Deng-Gao Lai, Adam Miranowicz, Franco Nori Phys. Rev. Lett., 132 , pp. 243602, 2024. @article{Lai24prl, title = {Nonreciprocal Topological Phonon Transfer Independent of Both Device Mass and Exceptional-Point Encircling Direction}, author = {Deng-Gao Lai and Adam Miranowicz and Franco Nori}, url = {https://link.aps.org/doi/10.1103/PhysRevLett.132.243602}, doi = {10.1103/PhysRevLett.132.243602}, year = {2024}, date = {2024-06-01}, journal = {Phys. Rev. Lett.}, volume = {132}, pages = {243602}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 255. | Weronika Andrzejewska, Paweł Wojciechowski, Mariya V Dobrotvorska, Szymon Murawka, Paweł Sobieszczyk, Mateusz Zelent, Mikołaj Lewandowski Directional growth of iron oxide nanowires on a vicinal copper surface Journal of Physics: Condensed Matter, 36 (34), pp. 345004, 2024. @article{Andrzejewska_2024, title = {Directional growth of iron oxide nanowires on a vicinal copper surface}, author = {Weronika Andrzejewska and Paweł Wojciechowski and Mariya V Dobrotvorska and Szymon Murawka and Paweł Sobieszczyk and Mateusz Zelent and Mikołaj Lewandowski}, url = {https://dx.doi.org/10.1088/1361-648X/ad3e58}, doi = {10.1088/1361-648X/ad3e58}, year = {2024}, date = {2024-05-30}, journal = {Journal of Physics: Condensed Matter}, volume = {36}, number = {34}, pages = {345004}, publisher = {IOP Publishing}, abstract = {Single-crystal magnetic nanostructures with well-defined shapes attract lots of interest due to their potential applications in magnetic and spintronic devices. However, development of methods allowing controlling their mutual crystallographic and geometric orientation constitutes a significant scientific challenge. One of the routes for obtaining such structures is to grow the materials epitaxially on naturally-structured supports, such as vicinal surfaces of single-crystal substrates. Iron oxides are among the most well-known magnetic materials which, depending on the phase, may exhibit ferro/ferri- or antiferromagnetic ordering. We have grown iron oxide nanowires on a Cu(410) single-crystal substrate faceted with molecular oxygen. Scanning tunneling microscopy and low energy electron diffraction revealed that the oxide grows in the [111] direction, along the step edges of the substrate and rotated by ±15° with respect to the [010] direction of copper atomic terraces (so that the the growing elongated structures are orientated parallel to each other). Notably, x-ray photoelectron spectroscopy confirmed that the nanowires represent the ferrimagnetic γ-Fe2O3 (maghemite) iron oxide phase, while micromagnetic simulations indicated that the wires are single-domain, with the easy magnetization axis orientated in-plane and along the long axis of the wire.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Single-crystal magnetic nanostructures with well-defined shapes attract lots of interest due to their potential applications in magnetic and spintronic devices. However, development of methods allowing controlling their mutual crystallographic and geometric orientation constitutes a significant scientific challenge. One of the routes for obtaining such structures is to grow the materials epitaxially on naturally-structured supports, such as vicinal surfaces of single-crystal substrates. Iron oxides are among the most well-known magnetic materials which, depending on the phase, may exhibit ferro/ferri- or antiferromagnetic ordering. We have grown iron oxide nanowires on a Cu(410) single-crystal substrate faceted with molecular oxygen. Scanning tunneling microscopy and low energy electron diffraction revealed that the oxide grows in the [111] direction, along the step edges of the substrate and rotated by ±15° with respect to the [010] direction of copper atomic terraces (so that the the growing elongated structures are orientated parallel to each other). Notably, x-ray photoelectron spectroscopy confirmed that the nanowires represent the ferrimagnetic γ-Fe2O3 (maghemite) iron oxide phase, while micromagnetic simulations indicated that the wires are single-domain, with the easy magnetization axis orientated in-plane and along the long axis of the wire. |
| 254. | Mathieu Moalic, Mateusz Zelent, Krzysztof Szulc, Maciej Krawczyk The role of non-uniform magnetization texture for magnon–magnon coupling in an antidot lattice Scientific Reports, 14 (1), pp. 11501, 2024, ISSN: 2045-2322. @article{moalic_role_2024, title = {The role of non-uniform magnetization texture for magnon–magnon coupling in an antidot lattice}, author = {Mathieu Moalic and Mateusz Zelent and Krzysztof Szulc and Maciej Krawczyk}, url = {https://www.nature.com/articles/s41598-024-61246-5}, doi = {10.1038/s41598-024-61246-5}, issn = {2045-2322}, year = {2024}, date = {2024-05-20}, urldate = {2024-05-23}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {11501}, abstract = {We numerically study the spin-wave dynamics in an antidot lattice based on a Co/Pd multilayer structure with reduced perpendicular magnetic anisotropy at the edges of the antidots. This structure forms a magnonic crystal with a periodic antidot pattern and a periodic magnetization configuration consisting of out-of-plane magnetized bulk and in-plane magnetized rims. Our results show a different behavior of spin waves in the bulk and in the rims under varying out-of-plane external magnetic field strength, revealing complex spin-wave spectra and hybridizations between the modes of these two subsystems. A particularly strong magnon–magnon coupling, due to exchange interactions, is found between the fundamental bulk spin-wave mode and the second-order radial rim modes. However, the dynamical coupling between the spin-wave modes at low frequencies, involving the first-order radial rim modes, is masked by the changes in the static magnetization at the bulk–rim interface with magnetic field changes. The study expands the horizons of magnonic-crystal research by combining periodic structural patterning and non-collinear magnetization texture to achieve strong magnon–magnon coupling, highlighting the significant role of exchange interactions in the hybridization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We numerically study the spin-wave dynamics in an antidot lattice based on a Co/Pd multilayer structure with reduced perpendicular magnetic anisotropy at the edges of the antidots. This structure forms a magnonic crystal with a periodic antidot pattern and a periodic magnetization configuration consisting of out-of-plane magnetized bulk and in-plane magnetized rims. Our results show a different behavior of spin waves in the bulk and in the rims under varying out-of-plane external magnetic field strength, revealing complex spin-wave spectra and hybridizations between the modes of these two subsystems. A particularly strong magnon–magnon coupling, due to exchange interactions, is found between the fundamental bulk spin-wave mode and the second-order radial rim modes. However, the dynamical coupling between the spin-wave modes at low frequencies, involving the first-order radial rim modes, is masked by the changes in the static magnetization at the bulk–rim interface with magnetic field changes. The study expands the horizons of magnonic-crystal research by combining periodic structural patterning and non-collinear magnetization texture to achieve strong magnon–magnon coupling, highlighting the significant role of exchange interactions in the hybridization. |
| 253. | Uladzislau Makartsou, Mateusz Gołębiewski, Urszula Guzowska, Alexander Stognij, Ryszard Gieniusz, Maciej Krawczyk Applied Physics Letters, 124 (19), pp. 192406, 2024, ISSN: 0003-6951. @article{10.1063/5.0195099, title = {Spin-wave self-imaging: Experimental and numerical demonstration of caustic and Talbot-like diffraction patterns}, author = {Uladzislau Makartsou and Mateusz Gołębiewski and Urszula Guzowska and Alexander Stognij and Ryszard Gieniusz and Maciej Krawczyk}, url = {https://doi.org/10.1063/5.0195099}, doi = {10.1063/5.0195099}, issn = {0003-6951}, year = {2024}, date = {2024-05-09}, journal = {Applied Physics Letters}, volume = {124}, number = {19}, pages = {192406}, abstract = {Extending the scope of the self-imaging phenomenon, traditionally associated with linear optics, to the domain of magnonics, this study presents the experimental demonstration and numerical analysis of spin-wave (SW) self-imaging in an in-plane magnetized yttrium iron garnet film. We explore this phenomenon using a setup in which a plane SW passes through a diffraction grating, and the resulting interference pattern is detected using Brillouin light scattering. We have varied the frequencies of the source dynamic magnetic field to discern the influence of the anisotropic dispersion relation and the caustic effect on the analyzed phenomenon. We found that at low frequencies and diffraction fields, the caustics determine the interference pattern. However, at large distances from the grating, when the waves of high diffraction order and number of slits contribute to the interference pattern, the self-imaging phenomenon and Talbot-like patterns are formed. This methodological approach not only sheds light on the behavior of SW interference under different conditions but also enhances our understanding of the SW self-imaging process in both isotropic and anisotropic media.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Extending the scope of the self-imaging phenomenon, traditionally associated with linear optics, to the domain of magnonics, this study presents the experimental demonstration and numerical analysis of spin-wave (SW) self-imaging in an in-plane magnetized yttrium iron garnet film. We explore this phenomenon using a setup in which a plane SW passes through a diffraction grating, and the resulting interference pattern is detected using Brillouin light scattering. We have varied the frequencies of the source dynamic magnetic field to discern the influence of the anisotropic dispersion relation and the caustic effect on the analyzed phenomenon. We found that at low frequencies and diffraction fields, the caustics determine the interference pattern. However, at large distances from the grating, when the waves of high diffraction order and number of slits contribute to the interference pattern, the self-imaging phenomenon and Talbot-like patterns are formed. This methodological approach not only sheds light on the behavior of SW interference under different conditions but also enhances our understanding of the SW self-imaging process in both isotropic and anisotropic media. |
| 252. | Agata Krzywicka, Tomasz P Polak Reentrant phase behavior in systems with density-induced tunneling Scientific Reports, 14 , pp. 10364 , 2024. @article{Krzywicka2024, title = {Reentrant phase behavior in systems with density-induced tunneling}, author = {Agata Krzywicka and Tomasz P Polak}, doi = {10.1038/s41598-024-60955-1}, year = {2024}, date = {2024-05-06}, journal = {Scientific Reports}, volume = {14}, pages = {10364 }, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 251. | Javier Argüello-Luengo, Utso Bhattacharya, Alessio Celi, Ravindra W. Chhajlany, Tobias Graß, Marcin Płodzień, Debraj Rakshit, Tymoteusz Salamon, Paolo Stornati, Leticia Tarruell, Maciej Lewenstein Synthetic dimensions for topological and quantum phases Communications Physics, 7 (1), pp. 143, 2024. @article{Arguello-Luengo2024-ip, title = {Synthetic dimensions for topological and quantum phases}, author = {Javier Argüello-Luengo and Utso Bhattacharya and Alessio Celi and Ravindra W. Chhajlany and Tobias Graß and Marcin P{ł}odzie{ń} and Debraj Rakshit and Tymoteusz Salamon and Paolo Stornati and Leticia Tarruell and Maciej Lewenstein}, url = {https://www.nature.com/articles/s42005-024-01636-3#citeas}, doi = {10.1038/s42005-024-01636-3}, year = {2024}, date = {2024-05-04}, journal = {Communications Physics}, volume = {7}, number = {1}, pages = {143}, abstract = {The concept of synthetic dimensions works particularly well in atomic physics, quantum optics, and photonics, where the internal degrees of freedom (Zeeman sublevels of the ground state, metastable excited states, or motional states for atoms, and angular momentum states or transverse modes for photons) provide the synthetic space. In this Perspective article we report on recent progress on studies of synthetic dimensions, mostly, but not only, based on the research realized around the Barcelona groups (ICFO, UAB), Donostia (DIPC), Poznan (UAM), Kraków (UJ), and Allahabad (HRI). We describe our attempts to design quantum simulators with synthetic dimensions, to mimic curved spaces, artificial gauge fields, lattice gauge theories, twistronics, quantum random walks, and more.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The concept of synthetic dimensions works particularly well in atomic physics, quantum optics, and photonics, where the internal degrees of freedom (Zeeman sublevels of the ground state, metastable excited states, or motional states for atoms, and angular momentum states or transverse modes for photons) provide the synthetic space. In this Perspective article we report on recent progress on studies of synthetic dimensions, mostly, but not only, based on the research realized around the Barcelona groups (ICFO, UAB), Donostia (DIPC), Poznan (UAM), Kraków (UJ), and Allahabad (HRI). We describe our attempts to design quantum simulators with synthetic dimensions, to mimic curved spaces, artificial gauge fields, lattice gauge theories, twistronics, quantum random walks, and more. |
| 250. | Bárbara Andrade, Utso Bhattacharya, Ravindra W. Chhajlany, Tobias Graß, Maciej Lewenstein Observing quantum many-body scars in random quantum circuits Phys. Rev. A, 109 , pp. 052602, 2024. @article{PhysRevA.109.052602, title = {Observing quantum many-body scars in random quantum circuits}, author = {Bárbara Andrade and Utso Bhattacharya and Ravindra W. Chhajlany and Tobias Graß{} and Maciej Lewenstein}, url = {https://link.aps.org/doi/10.1103/PhysRevA.109.052602}, doi = {10.1103/PhysRevA.109.052602}, year = {2024}, date = {2024-05-01}, journal = {Phys. Rev. A}, volume = {109}, pages = {052602}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 249. | Mateusz Gołębiewski, Riccardo Hertel, Massimiliano dÁquino, Vitaliy Vasyuchka, Mathias Weiler, Philipp Pirro, Maciej Krawczyk, Shunsuke Fukami, Hideo Ohno, Justin Llandro Collective Spin-Wave Dynamics in Gyroid Ferromagnetic Nanostructures ACS Applied Materials & Interfaces, 2024, ISSN: 1944-8244. @article{Gołębiewski2024, title = {Collective Spin-Wave Dynamics in Gyroid Ferromagnetic Nanostructures}, author = {Mateusz Gołębiewski and Riccardo Hertel and Massimiliano dÁquino and Vitaliy Vasyuchka and Mathias Weiler and Philipp Pirro and Maciej Krawczyk and Shunsuke Fukami and Hideo Ohno and Justin Llandro}, url = {https://doi.org/10.1021/acsami.4c02366}, doi = {10.1021/acsami.4c02366}, issn = {1944-8244}, year = {2024}, date = {2024-04-22}, journal = {ACS Applied Materials & Interfaces}, publisher = {American Chemical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |
| 248. | Piotr Trocha, Thibaut Jonckheere, Jérôme Rech, Thierry Martin Journal of Magnetism and Magnetic Materials, 596 , pp. 171922, 2024. @article{Trocha2024, title = {Out-of-equilibrium voltage and thermal bias response of a quantum dot hybrid system coupled to topological superconductor}, author = {Piotr Trocha and Thibaut Jonckheere and Jérôme Rech and Thierry Martin}, url = {https://www.sciencedirect.com/science/article/pii/S0304885324002130?via%3Dihub}, doi = {/10.1016/j.jmmm.2024.171922}, year = {2024}, date = {2024-04-15}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {596}, pages = {171922}, abstract = {We investigate theoretically the out-of-equilibrium transport properties of a single-level quantum dot coupled to a normal metal electrode and attached to a topological superconductor. Both voltage and thermal bias responses of the system in the nonequilibrium regime are studied. To obtain transport characteristics we used the nonequilibrium Green’s function approach. Particularly, we calculated the current and the corresponding differential conductance in two distinct cases. In the former situation, the charge current is induced by applying a bias voltage, whereas in the latter case it is generated by setting a temperature difference between the leads with no bias voltage. Moreover, strong diode effect in thermally generated current is found and non-equilibrium thermopower is analyzed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We investigate theoretically the out-of-equilibrium transport properties of a single-level quantum dot coupled to a normal metal electrode and attached to a topological superconductor. Both voltage and thermal bias responses of the system in the nonequilibrium regime are studied. To obtain transport characteristics we used the nonequilibrium Green’s function approach. Particularly, we calculated the current and the corresponding differential conductance in two distinct cases. In the former situation, the charge current is induced by applying a bias voltage, whereas in the latter case it is generated by setting a temperature difference between the leads with no bias voltage. Moreover, strong diode effect in thermally generated current is found and non-equilibrium thermopower is analyzed. |
| 247. | Kacper Wrześniewski, Ireneusz Weymann Scientific Reports, 14 (7815), 2024. @article{Wrześniewski2024, title = {Cross-correlations between currents and tunnel magnetoresistance in interacting double quantum dot-Majorana wire system}, author = {Kacper Wrześniewski and Ireneusz Weymann }, url = {https://link.springer.com/article/10.1038/s41598-024-58344-9}, doi = {10.1038/s41598-024-58344-9}, year = {2024}, date = {2024-04-03}, journal = {Scientific Reports}, volume = {14}, number = {7815}, abstract = {We theoretically investigate the spin and charge transport properties of a double quantum dot coupled to distinct edges of the nanowire hosting Majorana zero-energy modes. The focus is on the analysis of the currents flowing through the left and right junctions and their cross-correlations. We show that the system reveals very different transport properties depending on the detuning protocol of the quantum dot energy levels. For the symmetric detuning, the current dependencies reveal only two maxima associated with resonant tunneling, and currents in the left and right arms of the system reveal weak positive cross-correlations. On the other hand, for antisymmetric detuning, the flow of electrons into drains is maximized and strongly correlated in one bias voltage direction, while for the opposite bias direction a spin blockade is predicted. Furthermore, we observe a suppression of the current cross-correlations at a highly symmetric detuning point, indicating the involvement of the Majorana zero-energy modes in the transport processes. To gain insight into the role of the spin polarization of the Majorana edge states, we analyze the spin-dependent transport characteristics by considering the relationship between the spin canting angle, which describes the coupling of the Majorana modes to the spin of the quantum dots, and the magnetic configurations of the ferromagnetic drains. Moreover, we examine the non-local zero bias anomaly in the differential conductance, detailed analysis of which revealed a specific operational mode of the device that can facilitate the identification of the Majorana presence in the quantum dot-Majorana wire system. Finally, we also consider the transport properties in different magnetic configurations of the system and discuss the behavior of the associated tunnel magnetoresistance.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We theoretically investigate the spin and charge transport properties of a double quantum dot coupled to distinct edges of the nanowire hosting Majorana zero-energy modes. The focus is on the analysis of the currents flowing through the left and right junctions and their cross-correlations. We show that the system reveals very different transport properties depending on the detuning protocol of the quantum dot energy levels. For the symmetric detuning, the current dependencies reveal only two maxima associated with resonant tunneling, and currents in the left and right arms of the system reveal weak positive cross-correlations. On the other hand, for antisymmetric detuning, the flow of electrons into drains is maximized and strongly correlated in one bias voltage direction, while for the opposite bias direction a spin blockade is predicted. Furthermore, we observe a suppression of the current cross-correlations at a highly symmetric detuning point, indicating the involvement of the Majorana zero-energy modes in the transport processes. To gain insight into the role of the spin polarization of the Majorana edge states, we analyze the spin-dependent transport characteristics by considering the relationship between the spin canting angle, which describes the coupling of the Majorana modes to the spin of the quantum dots, and the magnetic configurations of the ferromagnetic drains. Moreover, we examine the non-local zero bias anomaly in the differential conductance, detailed analysis of which revealed a specific operational mode of the device that can facilitate the identification of the Majorana presence in the quantum dot-Majorana wire system. Finally, we also consider the transport properties in different magnetic configurations of the system and discuss the behavior of the associated tunnel magnetoresistance. |
| 246. | Deng-Gao Lai, C -H Wang, B -P Hou, Adam Miranowicz, Franco Nori Exceptional refrigeration of motions beyond their mass and temperature limitations Optica, 11 (4), pp. 485–491, 2024. @article{Lai2024b, title = {Exceptional refrigeration of motions beyond their mass and temperature limitations}, author = {Deng-Gao Lai and C -H Wang and B -P Hou and Adam Miranowicz and Franco Nori}, url = {https://opg.optica.org/optica/abstract.cfm?URI=optica-11-4-485}, doi = {10.1364/OPTICA.495199}, year = {2024}, date = {2024-04-01}, journal = {Optica}, volume = {11}, number = {4}, pages = {485--491}, publisher = {Optica Publishing Group}, abstract = {Coaxing vibrations in the regimes of both large mass and high temperature into their motional quantum ground states is extremely challenging, because it requires an ultra-high optical power, which introduces extraneous excessive heating and intricate instabilities. Here we propose how to overcome these obstacles and cool vibrational networks by simply harnessing the power of an exceptional point (EP) induced in parity-time symmetric structures; and we reveal its exceptional cooling properties otherwise unachievable in conventional devices. In stark contrast to standard-cooling protocols, a three orders-of-magnitude amplification in net cooling rates arises from the EP-cooling mechanism, without which it vanishes. Remarkably, our EP cooling is nearly immune to both resonator mass and environmental temperature, and this overthrows the consensus that poor intrinsic factors and rugged extrinsic environment suppress cooling channels. Our study offers the possibility of isolating and engineering motional properties of large-mass and high-temperature objects for various applications in optical and acoustic sensing, gravimetry, and inertial navigation.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Coaxing vibrations in the regimes of both large mass and high temperature into their motional quantum ground states is extremely challenging, because it requires an ultra-high optical power, which introduces extraneous excessive heating and intricate instabilities. Here we propose how to overcome these obstacles and cool vibrational networks by simply harnessing the power of an exceptional point (EP) induced in parity-time symmetric structures; and we reveal its exceptional cooling properties otherwise unachievable in conventional devices. In stark contrast to standard-cooling protocols, a three orders-of-magnitude amplification in net cooling rates arises from the EP-cooling mechanism, without which it vanishes. Remarkably, our EP cooling is nearly immune to both resonator mass and environmental temperature, and this overthrows the consensus that poor intrinsic factors and rugged extrinsic environment suppress cooling channels. Our study offers the possibility of isolating and engineering motional properties of large-mass and high-temperature objects for various applications in optical and acoustic sensing, gravimetry, and inertial navigation. |
| 245. | Nikhil Kumar, Paweł Gruszecki, Mateusz Gołębiewski, Jarosław W. Kłos, Maciej Krawczyk Exciting High-Frequency Short-Wavelength Spin Waves using High Harmonics of a Magnonic Cavity Mode Advanced Quantum Technologies, n/a (n/a), pp. 2400015, 2024. @article{https://doi.org/10.1002/qute.202400015, title = {Exciting High-Frequency Short-Wavelength Spin Waves using High Harmonics of a Magnonic Cavity Mode}, author = {Nikhil Kumar and Paweł Gruszecki and Mateusz Gołębiewski and Jarosław W. Kłos and Maciej Krawczyk}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/qute.202400015}, doi = {https://doi.org/10.1002/qute.202400015}, year = {2024}, date = {2024-03-29}, journal = {Advanced Quantum Technologies}, volume = {n/a}, number = {n/a}, pages = {2400015}, abstract = {Abstract Spin waves (SWs) are promising objects for signal processing and future quantum technologies due to their high microwave frequencies with corresponding nanoscale wavelengths. However, the nano-wavelength SWs generated so far are limited to low frequencies. In the paper, using micromagnetic simulations, it is shown that a microwave-pumped SW mode confined to the cavity of a thin film magnonic crystal (MC) can be used to generate waves at tens of GHz and wavelengths well below 50 nm. These multi-frequency harmonics of the fundamental cavity mode are generated when the amplitude of the pumping microwave field exceeds a threshold, and their intensities then scale linearly with the field intensity. The frequency of the cavity mode is equal to the ferromagnetic resonance frequency of the planar ferromagnetic film, which overlaps with the magnonic bandgap, providing an efficient mechanism for confinement and magnetic field tunability. The effect reaches saturation when the microstrip feed line covers the entire cavity, making the system feasible for realization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Abstract Spin waves (SWs) are promising objects for signal processing and future quantum technologies due to their high microwave frequencies with corresponding nanoscale wavelengths. However, the nano-wavelength SWs generated so far are limited to low frequencies. In the paper, using micromagnetic simulations, it is shown that a microwave-pumped SW mode confined to the cavity of a thin film magnonic crystal (MC) can be used to generate waves at tens of GHz and wavelengths well below 50 nm. These multi-frequency harmonics of the fundamental cavity mode are generated when the amplitude of the pumping microwave field exceeds a threshold, and their intensities then scale linearly with the field intensity. The frequency of the cavity mode is equal to the ferromagnetic resonance frequency of the planar ferromagnetic film, which overlaps with the magnonic bandgap, providing an efficient mechanism for confinement and magnetic field tunability. The effect reaches saturation when the microstrip feed line covers the entire cavity, making the system feasible for realization. |
| 244. | Chia-Yi Ju, Adam Miranowicz, Yueh-Nan Chen, Guang-Yin Chen, Franco Nori Emergent parallel transport and curvature in Hermitian and non-Hermitian quantum mechanics Quantum, 8 , pp. 1277, 2024. @article{Ju2024, title = {Emergent parallel transport and curvature in Hermitian and non-Hermitian quantum mechanics}, author = {Chia-Yi Ju and Adam Miranowicz and Yueh-Nan Chen and Guang-Yin Chen and Franco Nori}, url = {https://quantum-journal.org/papers/q-2024-03-13-1277/}, doi = {10.22331/q-2024-03-13-1277}, year = {2024}, date = {2024-03-13}, journal = {Quantum}, volume = {8}, pages = {1277}, abstract = {Studies have shown that the Hilbert spaces of non-Hermitian systems require nontrivial metrics. Here, we demonstrate how evolution dimensions, in addition to time, can emerge naturally from a geometric formalism. Specifically, in this formalism, Hamiltonians can be interpreted as a Christoffel symbol-like operators, and the Schroedinger equation as a parallel transport in this formalism. We then derive the evolution equations for the states and metrics along the emergent dimensions and find that the curvature of the Hilbert space bundle for any given closed system is locally flat. Finally, we show that the fidelity susceptibilities and the Berry curvatures of states are related to these emergent parallel transports.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Studies have shown that the Hilbert spaces of non-Hermitian systems require nontrivial metrics. Here, we demonstrate how evolution dimensions, in addition to time, can emerge naturally from a geometric formalism. Specifically, in this formalism, Hamiltonians can be interpreted as a Christoffel symbol-like operators, and the Schroedinger equation as a parallel transport in this formalism. We then derive the evolution equations for the states and metrics along the emergent dimensions and find that the curvature of the Hilbert space bundle for any given closed system is locally flat. Finally, we show that the fidelity susceptibilities and the Berry curvatures of states are related to these emergent parallel transports. |
| 243. | Wei Qin, Adam Miranowicz, Franco Nori Proposal of ensemble qubits with two-atom decay New Journal of Physics, 26 , pp. 033006, 2024. @article{Qin2024, title = {Proposal of ensemble qubits with two-atom decay}, author = {Wei Qin and Adam Miranowicz and Franco Nori}, url = {https://iopscience.iop.org/article/10.1088/1367-2630/ad2bad}, doi = {10.1088/1367-2630/ad2bad}, year = {2024}, date = {2024-03-08}, journal = {New Journal of Physics}, volume = {26}, pages = {033006}, abstract = {We propose and analyze a novel approach to implement ensemble qubits. The required anharmonicity is provided by a simultaneous decay of two atoms (i.e. two-atom decay), which is achieved by fully quantum degenerate parametric amplification. For an atomic ensemble, the two-atom decay generates and stabilizes a 2D quantum manifold, which is spanned by the ground and single-excited superradiant states. Moreover, this nonlinear decay process can strongly suppress transitions to higher-excited superradiant states, and convert residual transitions into an effective decay from the single-excitation superradiant state to the ground state. Our method does not require Rydberg dipole blockade and, thus, strong atom-atom interactions, compared to previous work. This indicates that it can be applied to typical atomic or spin ensembles in simple experimental setups. Remarkably, our idea is compatible with the cavity protection mechanism, and therefore spin dephasing due to inhomogeneous broadening can be strongly suppressed. The presented ensemble qubit provides a new platform for quantum information processing, and also extends the range of applications of atomic or spin ensembles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We propose and analyze a novel approach to implement ensemble qubits. The required anharmonicity is provided by a simultaneous decay of two atoms (i.e. two-atom decay), which is achieved by fully quantum degenerate parametric amplification. For an atomic ensemble, the two-atom decay generates and stabilizes a 2D quantum manifold, which is spanned by the ground and single-excited superradiant states. Moreover, this nonlinear decay process can strongly suppress transitions to higher-excited superradiant states, and convert residual transitions into an effective decay from the single-excitation superradiant state to the ground state. Our method does not require Rydberg dipole blockade and, thus, strong atom-atom interactions, compared to previous work. This indicates that it can be applied to typical atomic or spin ensembles in simple experimental setups. Remarkably, our idea is compatible with the cavity protection mechanism, and therefore spin dephasing due to inhomogeneous broadening can be strongly suppressed. The presented ensemble qubit provides a new platform for quantum information processing, and also extends the range of applications of atomic or spin ensembles. |
| 242. | Arnab Laha, Adam Miranowicz, R. K. Varshney, Somnath Ghosh Correlated nonreciprocity around conjugate exceptional points Phys. Rev. A, 109 , pp. 033511, 2024. @article{Laha2024, title = {Correlated nonreciprocity around conjugate exceptional points}, author = {Arnab Laha and Adam Miranowicz and R. K. Varshney and Somnath Ghosh}, url = {https://link.aps.org/doi/10.1103/PhysRevA.109.033511}, doi = {10.1103/PhysRevA.109.033511}, year = {2024}, date = {2024-03-08}, journal = {Phys. Rev. A}, volume = {109}, pages = {033511}, abstract = {The occurrence of exceptional points (EPs) is a fascinating non-Hermitian feature of open systems. A level-repulsion phenomenon between two complex states of an open system can be realized by positioning an EP and its time-reversal ( T ) conjugate pair in the underlying parameter space. Here, we report interesting nonreciprocal responses of such two conjugate EPs by using a dual-mode planar waveguide system having two T -symmetric active variants concerning the transverse gain-loss profiles. We specifically reveal an all-optical scheme to achieve correlative nonreciprocal light dynamics by using the reverse chirality of two dynamically encircled conjugate EPs in the presence of local nonlinearity. A specific nonreciprocal correlation between two designed T -symmetric waveguide variants is established in terms of their unidirectional transfer of light with a precise selection of modes. Here, the unconventional reverse chiral properties of two conjugate EPs allow the nonreciprocal transmission of two selective modes in the opposite directions of the underlying waveguide variants. An explicit dependence of the nonlinearity level on a significant enhancement of the nonreciprocity in terms of an isolation ratio is explored by investigating the effects of both local Kerr-type and saturable nonlinearities (considered separately). The physical insights and implications of harnessing the features of conjugate EPs in nonlinear optical systems can enable the growth and development of a versatile platform for building nonreciprocal components and devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The occurrence of exceptional points (EPs) is a fascinating non-Hermitian feature of open systems. A level-repulsion phenomenon between two complex states of an open system can be realized by positioning an EP and its time-reversal ( T ) conjugate pair in the underlying parameter space. Here, we report interesting nonreciprocal responses of such two conjugate EPs by using a dual-mode planar waveguide system having two T -symmetric active variants concerning the transverse gain-loss profiles. We specifically reveal an all-optical scheme to achieve correlative nonreciprocal light dynamics by using the reverse chirality of two dynamically encircled conjugate EPs in the presence of local nonlinearity. A specific nonreciprocal correlation between two designed T -symmetric waveguide variants is established in terms of their unidirectional transfer of light with a precise selection of modes. Here, the unconventional reverse chiral properties of two conjugate EPs allow the nonreciprocal transmission of two selective modes in the opposite directions of the underlying waveguide variants. An explicit dependence of the nonlinearity level on a significant enhancement of the nonreciprocity in terms of an isolation ratio is explored by investigating the effects of both local Kerr-type and saturable nonlinearities (considered separately). The physical insights and implications of harnessing the features of conjugate EPs in nonlinear optical systems can enable the growth and development of a versatile platform for building nonreciprocal components and devices. |
| 241. | Anand Manaparambil, Ireneusz Weymann Spin-resolved nonequilibrium thermopower of asymmetric nanojunctions Phys. Rev. B, 109 , pp. 115402, 2024. @article{Manaparambil2024b, title = {Spin-resolved nonequilibrium thermopower of asymmetric nanojunctions}, author = {Anand Manaparambil and Ireneusz Weymann}, url = {https://journals.aps.org/prb/abstract/10.1103/PhysRevB.109.115402}, doi = {10.1103/PhysRevB.109.115402}, year = {2024}, date = {2024-03-04}, journal = {Phys. Rev. B}, volume = {109}, pages = { 115402}, abstract = {The spin-resolved thermoelectric transport properties of correlated nanoscale junctions, consisting of a quantum dot/molecule asymmetrically coupled to external ferromagnetic contacts, are studied theoretically in the far-from-equilibrium regime. One of the leads is assumed to be strongly coupled to the quantum dot resulting in the development of the Kondo effect. The spin-dependent current flowing through the system, as well as the thermoelectric properties, are calculated by performing a perturbation expansion with respect to the weakly coupled electrode, while the Kondo correlations are captured accurately by using the numerical renormalization group method. In particular, we determine the differential and nonequilibrium Seebeck effects of the considered system in different magnetic configurations and uncover the crucial role of spin-dependent tunneling on the device performance. Moreover, by allowing for the spin accumulation in the leads, which gives rise to finite spin bias, we shed light on the behavior of the nonequilibrium spin Seebeck effect. In particular, we predict new sign changes of the spin-resolved Seebeck effect in the nonlinear response regime, which stem from the interplay of exchange field and finite voltage and temperature gradients.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The spin-resolved thermoelectric transport properties of correlated nanoscale junctions, consisting of a quantum dot/molecule asymmetrically coupled to external ferromagnetic contacts, are studied theoretically in the far-from-equilibrium regime. One of the leads is assumed to be strongly coupled to the quantum dot resulting in the development of the Kondo effect. The spin-dependent current flowing through the system, as well as the thermoelectric properties, are calculated by performing a perturbation expansion with respect to the weakly coupled electrode, while the Kondo correlations are captured accurately by using the numerical renormalization group method. In particular, we determine the differential and nonequilibrium Seebeck effects of the considered system in different magnetic configurations and uncover the crucial role of spin-dependent tunneling on the device performance. Moreover, by allowing for the spin accumulation in the leads, which gives rise to finite spin bias, we shed light on the behavior of the nonequilibrium spin Seebeck effect. In particular, we predict new sign changes of the spin-resolved Seebeck effect in the nonlinear response regime, which stem from the interplay of exchange field and finite voltage and temperature gradients. |
| 240. | Marek Kopciuch, Magdalena Smolis, Adam Miranowicz, Szymon Pustelny Optimized optical tomography of quantum states of a room-temperature alkali-metal vapor Phys. Rev. A, 109 , pp. 032402, 2024. @article{Kopciuch2024, title = {Optimized optical tomography of quantum states of a room-temperature alkali-metal vapor}, author = {Marek Kopciuch and Magdalena Smolis and Adam Miranowicz and Szymon Pustelny}, url = {https://link.aps.org/doi/10.1103/PhysRevA.109.032402}, doi = {10.1103/PhysRevA.109.032402}, year = {2024}, date = {2024-03-01}, journal = {Phys. Rev. A}, volume = {109}, pages = {032402}, abstract = {We demonstrate an experimental technique for the quantum-state tomography of the collective qutrit states of a room-temperature alkali-metal vapor. It is based on the measurements of the polarization of light traversing the vapor subjected to a magnetic field. To assess the technique's robustness against errors, experimental investigations are supported with numerical simulations. This not only allows us to determine the fidelity of the reconstructed states, but also to analyze the quality of the reconstruction for specific experimental parameters, such as light tuning and the number of measurements. By utilizing the conditional number, we demonstrate that the reconstruction robustness can be optimized by a proper adjustment of experimental parameters, and further improvement is possible with the repetition of specific measurements. Our results demonstrate the potential of this high-fidelity reconstruction method of quantum states of room-temperature atomic vapors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We demonstrate an experimental technique for the quantum-state tomography of the collective qutrit states of a room-temperature alkali-metal vapor. It is based on the measurements of the polarization of light traversing the vapor subjected to a magnetic field. To assess the technique's robustness against errors, experimental investigations are supported with numerical simulations. This not only allows us to determine the fidelity of the reconstructed states, but also to analyze the quality of the reconstruction for specific experimental parameters, such as light tuning and the number of measurements. By utilizing the conditional number, we demonstrate that the reconstruction robustness can be optimized by a proper adjustment of experimental parameters, and further improvement is possible with the repetition of specific measurements. Our results demonstrate the potential of this high-fidelity reconstruction method of quantum states of room-temperature atomic vapors. |
| 239. | Yuma Watanabe, Utso Bhattacharya, Ravindra W. Chhajlany, Javier Argüello-Luengo, Maciej Lewenstein, Tobias Graß Competing order in two-band Bose-Hubbard chains with extended-range interactions Phys. Rev. B, 109 , pp. L100507, 2024. @article{PhysRevB.109.L100507, title = {Competing order in two-band Bose-Hubbard chains with extended-range interactions}, author = {Yuma Watanabe and Utso Bhattacharya and Ravindra W. Chhajlany and Javier Argüello-Luengo and Maciej Lewenstein and Tobias Graß}, url = {https://link.aps.org/doi/10.1103/PhysRevB.109.L100507}, doi = {10.1103/PhysRevB.109.L100507}, year = {2024}, date = {2024-03-01}, journal = {Phys. Rev. B}, volume = {109}, pages = {L100507}, publisher = {American Physical Society}, keywords = {}, pubstate = {published}, tppubtype = {article} } |