Dr hab. Paweł Gruszecki

Dr hab. Paweł Gruszecki

Department of Physics of Nanostructures

Tel: +48 61 829 5192
Loc: wing G, second floor, room 276
Email: gruszecki@amu.edu.pl

Scientific degrees

Habilitation – 2024
PhD in Physics (Adam Mickiewicz University) – 2017
MSc in Physics (Adam Mickiewicz University) – 2015
MSc in Automatic Control and Robotics (Poznań University of Technology) – 2011

Research interests

Keywords: magnonics, spin waves, magnetization dynamics

In my research, I am interested in spin wave related phenomena. I focus on linear and non-linear spin wave optics and spin wave dynamics in non-uniform textures of magnetization, including the study of spin waves in textures characterized by space and space-time periodicity.

Research stays

Donetsk Physical and Technical Institute of the National Academy of Sciences of Ukraine (Donetsk) – 1 month
Kotelnikov Institute of Radio-engineering and Electronics of Russian Academy of Science, group of prof. S.A. Nikitov (Moscow) – 2 months
Institute of Magnetism, National Academy of Sciences of Ukraine in Kiev (Kiev) – 3 months
Igor Sikorsky Kyiv Polytechnic Institute (Kiev) – 4 months

Scientific achievements

Fellowship for outstanding young scientists of the Polish Ministry of Science and Higher Education (2019)
The distinction of PhD thesis by Polish Physical Society (2018)
Fellowship for young scientists granted by the city of Poznan (2017)
Polish Ministry of Science and Higher Education scholarship for postgraduate students (2016)
Fellowship of the Foundation of Adam Mickiewicz University in Poznan (2015)
Rector’s award for scientific research (Adam Mickiewicz University in Poznan) (2015)
Rector’s award for scientific research (Adam Mickiewicz University in Poznan) (2014)

Projects

Paweł Gruszecki

Magnonic Artificial Neural Networks and Gate Arrays (MANNGA)

2024 - 2025, (EU Research and Innovation Programme Horizon Europe (Hop-on Facility call HORIZON-WIDERA-2023-ACCESS-06 and HORIZON-CL4-2021-DIGITAL-EMERGING-01), grant agreement no. 101070347 (MANNGA). Budget: 301 250.00 EURO).

Abstract | Links

Paweł Gruszecki

Novel environment for spin wave propagation: from periodic magnetization textures towards space-time magnonic crystals

2020 - 2023, (NCN Sonata 15, No. 2019/35/D/ST3/03729, budget: 938 928,00 PLN).

Abstract | Links

@misc{Gruszecki2023,
title = {Novel environment for spin wave propagation: from periodic magnetization textures towards space-time magnonic crystals},
author = {Paweł Gruszecki},
url = {https://zfn.web.amu.edu.pl/sonata-15/},
year = {2023},
date = {2023-12-01},
abstract = {A unique property of spin waves (SWs) is the fact that they propagate in magnetic media. Features of an environment for SWs can be easily molded, e.g., by the external factors like the magnetic field, but also by the internal magnetization texture. One of the efficient ways to modulate the effective media properties is the introduction of periodical modulation of them in the space. In the case of SWs, such media are called magnonic crystals (MCs). The concept of periodic modulation was just recently extended from space into space-time, leading to the idea of a time crystal by Wilczek in 2012. The definition of a time crystalline structure is deduced from ordinary space crystals where the critical criterion for the formation of a time-crystal is the breaking of the time translation symmetry (like spatial translation symmetry break is essential for ordinary space crystals). The combination of space and time symmetry breakings defines a so-called Space-Time Crystal (STC) that exhibits periodicity in space and time. In the frame of this Project, we unite the fundamental STC concept within the quantum regime with the world of magnonics introducing space-time MCs (STMCs) and present an exceptional case of nonlinear wave physics in a comparatively large structure. The general objective of this Project is the analysis of SW dynamics in magnetization textures that are, firstly, periodical in space, and, ultimately, in a new class of magnetization textures that are periodical both in space and time. The main research hypothesis is based on the assumption regarding a unique potential of nonuniform magnetization textures, especially those exhibiting space-time periodicity, as a medium for SW propagation.

We will study the properties of SW propagation along domain walls of different internal structures, starting from a single domain wall and, then, focusing on various periodical magnetization textures that can be either uniform or non-uniform across the thickness, i.e., we will study magnetization textures from periodic aligned stripe domains separated by narrow domain walls to spiral domain patterns requiring antisymmetric exchange interaction, so-called Dzyaloshinskii–Moriya interaction (DMI) to be stabilized. In these studies, the main Focus will be paid on the systems with perpendicular magnetocrystalline anisotropy (PMA) and DMI. Multifunctionality of single and multiple domain walls, as nanochannels with nonreciprocal properties supporting twisted SW beams and as a source of SWs, is expected to be achieved. The tenability of the SW spectrum and propagation characteristics of a periodical in one space dimension magnetization textures will be studied. The special attention, however, will be paid to a new class of magnetization textures that are both periodic in time and space. Various scenarios of condensation of these systems and their influence on SW dynamics will be extensively studied.

In this Project, we will address a few important issues in magnonics and in physics, in general. Firstly, we will study SW channeling in ultra-narrow single-mode waveguides created by domain walls of various internal structures focusing on their nonreciprocal properties and existence of SW modes behaving as twisted beams, i.e., beams with a definite and controllable orbital angular momentum. Secondly, we will employ domain walls to excite sub 100 nm wavelength SWs, which is another big challenge in magnonics nowadays. Thirdly, we will analyze how the magnetic properties of the media influence both magnetization statics and dynamics. Finally, we will use the acquired knowledge to analyze the condensation of a periodical in both space and time magnetization textures, and then their features for SW propagation. We will verify whether the STMCs form band structures at room temperature and if magnons interact with the lattice of STMCs like in regular crystals. The results of this Project will provide progress concerning state-of-the-art and ensure a significant contribution to the development of magnonics. Additionally, we hope, that our research can promise outstanding new opportunities in fundamental research in nonlinear wave physics.

The research bases on micromagnetic simulations supported by semi-analytical analysis of SW dynamics combined with atomistic simulations. Although the Project mainly bases on the theoretical and numerical investigation, the research will also be conducted in collaboration with experimental groups whenever possible.},
howpublished = {2020},
note = {NCN Sonata 15, No. 2019/35/D/ST3/03729, budget: 938 928,00 PLN},
keywords = {},
pubstate = {published},
tppubtype = {misc}
}

A unique property of spin waves (SWs) is the fact that they propagate in magnetic media. Features of an environment for SWs can be easily molded, e.g., by the external factors like the magnetic field, but also by the internal magnetization texture. One of the efficient ways to modulate the effective media properties is the introduction of periodical modulation of them in the space. In the case of SWs, such media are called magnonic crystals (MCs). The concept of periodic modulation was just recently extended from space into space-time, leading to the idea of a time crystal by Wilczek in 2012. The definition of a time crystalline structure is deduced from ordinary space crystals where the critical criterion for the formation of a time-crystal is the breaking of the time translation symmetry (like spatial translation symmetry break is essential for ordinary space crystals). The combination of space and time symmetry breakings defines a so-called Space-Time Crystal (STC) that exhibits periodicity in space and time. In the frame of this Project, we unite the fundamental STC concept within the quantum regime with the world of magnonics introducing space-time MCs (STMCs) and present an exceptional case of nonlinear wave physics in a comparatively large structure. The general objective of this Project is the analysis of SW dynamics in magnetization textures that are, firstly, periodical in space, and, ultimately, in a new class of magnetization textures that are periodical both in space and time. The main research hypothesis is based on the assumption regarding a unique potential of nonuniform magnetization textures, especially those exhibiting space-time periodicity, as a medium for SW propagation.

We will study the properties of SW propagation along domain walls of different internal structures, starting from a single domain wall and, then, focusing on various periodical magnetization textures that can be either uniform or non-uniform across the thickness, i.e., we will study magnetization textures from periodic aligned stripe domains separated by narrow domain walls to spiral domain patterns requiring antisymmetric exchange interaction, so-called Dzyaloshinskii–Moriya interaction (DMI) to be stabilized. In these studies, the main Focus will be paid on the systems with perpendicular magnetocrystalline anisotropy (PMA) and DMI. Multifunctionality of single and multiple domain walls, as nanochannels with nonreciprocal properties supporting twisted SW beams and as a source of SWs, is expected to be achieved. The tenability of the SW spectrum and propagation characteristics of a periodical in one space dimension magnetization textures will be studied. The special attention, however, will be paid to a new class of magnetization textures that are both periodic in time and space. Various scenarios of condensation of these systems and their influence on SW dynamics will be extensively studied.

In this Project, we will address a few important issues in magnonics and in physics, in general. Firstly, we will study SW channeling in ultra-narrow single-mode waveguides created by domain walls of various internal structures focusing on their nonreciprocal properties and existence of SW modes behaving as twisted beams, i.e., beams with a definite and controllable orbital angular momentum. Secondly, we will employ domain walls to excite sub 100 nm wavelength SWs, which is another big challenge in magnonics nowadays. Thirdly, we will analyze how the magnetic properties of the media influence both magnetization statics and dynamics. Finally, we will use the acquired knowledge to analyze the condensation of a periodical in both space and time magnetization textures, and then their features for SW propagation. We will verify whether the STMCs form band structures at room temperature and if magnons interact with the lattice of STMCs like in regular crystals. The results of this Project will provide progress concerning state-of-the-art and ensure a significant contribution to the development of magnonics. Additionally, we hope, that our research can promise outstanding new opportunities in fundamental research in nonlinear wave physics.

The research bases on micromagnetic simulations supported by semi-analytical analysis of SW dynamics combined with atomistic simulations. Although the Project mainly bases on the theoretical and numerical investigation, the research will also be conducted in collaboration with experimental groups whenever possible.

Publications

2024
25.	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. Links \| BibTeX @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} } Close https://link.aps.org/doi/10.1103/PhysRevB.110.184410 doi:10.1103/PhysRevB.110.184410 Close
24.	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 Reconfigurable magnonic crystals: Spin wave propagation in Pt/Co multilayer in saturated and stripe domain phase APL Materials, 12 (11), pp. 111106, 2024, ISSN: 2166-532X. Abstract \| Links \| BibTeX @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} } Close 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. Close https://doi.org/10.1063/5.0227380 doi:10.1063/5.0227380 Close
23.	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. Abstract \| Links \| BibTeX @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} } Close 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. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/qute.202400015 doi:https://doi.org/10.1002/qute.202400015 Close
2023
22.	A K Dhiman, R Gieniusz, J Kisielewski, P Mazalski, M Matczak, F Stobiecki, Paweł Gruszecki, Maciej Krawczyk, A Lynnyk, A Maziewski Hysteresis of magnetization statics and dynamics in [Pt/Co] multilayer Journal of Magnetism and Magnetic Materials, 587 , pp. 171338, 2023, ISSN: 0304-8853. Abstract \| Links \| BibTeX @article{DHIMAN2023171338, title = {Hysteresis of magnetization statics and dynamics in [Pt/Co] multilayer}, author = {A K Dhiman and R Gieniusz and J Kisielewski and P Mazalski and M Matczak and F Stobiecki and Paweł Gruszecki and Maciej Krawczyk and A Lynnyk and A Maziewski}, url = {https://www.sciencedirect.com/science/article/pii/S0304885323009885}, doi = {https://doi.org/10.1016/j.jmmm.2023.171338}, issn = {0304-8853}, year = {2023}, date = {2023-10-15}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {587}, pages = {171338}, abstract = {The magnetic multilayer of Co separated by thin spacer layer of Pt was deposited by DC-magnetron sputtering. From the longitudinal magneto-optical Kerr effect based magnetometry and microscopy as well as magnetic force microscopy, the hybrid magnetization structure was deduced: the large size, micrometer scale magnetic domains with in-plane “core magnetization” patterned by nanometer scale domains with out-of-plane components. The hysteresis as a function of in-plane applied magnetic field of both: (i) magnetization curve measured by Superconducting Quantum Interference Device and (ii) dynamic responses measured by broadband Vector Network Analyzer spectroscopy were observed. The experimental results are well described by micromagnetic simulations. These magnetic history dependent effects were explained by magnetization cores, with in plane component, switching.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The magnetic multilayer of Co separated by thin spacer layer of Pt was deposited by DC-magnetron sputtering. From the longitudinal magneto-optical Kerr effect based magnetometry and microscopy as well as magnetic force microscopy, the hybrid magnetization structure was deduced: the large size, micrometer scale magnetic domains with in-plane “core magnetization” patterned by nanometer scale domains with out-of-plane components. The hysteresis as a function of in-plane applied magnetic field of both: (i) magnetization curve measured by Superconducting Quantum Interference Device and (ii) dynamic responses measured by broadband Vector Network Analyzer spectroscopy were observed. The experimental results are well described by micromagnetic simulations. These magnetic history dependent effects were explained by magnetization cores, with in plane component, switching. Close https://www.sciencedirect.com/science/article/pii/S0304885323009885 doi:https://doi.org/10.1016/j.jmmm.2023.171338 Close
21.	Krzysztof Sobucki, Wojciech Śmigaj, Piotr Graczyk, Maciej Krawczyk, Paweł Gruszecki Magnon-Optic Effects with Spin-Wave Leaky Modes: Tunable Goos-Hänchen Shift and Wood’s Anomaly Nano Letters, 23 (15), pp. 6979-6984, 2023, (PMID: 37523860). Abstract \| Links \| BibTeX @article{doi:10.1021/acs.nanolett.3c01592, title = {Magnon-Optic Effects with Spin-Wave Leaky Modes: Tunable Goos-Hänchen Shift and Wood’s Anomaly}, author = {Krzysztof Sobucki and Wojciech Śmigaj and Piotr Graczyk and Maciej Krawczyk and Paweł Gruszecki}, url = {https://doi.org/10.1021/acs.nanolett.3c01592}, doi = {10.1021/acs.nanolett.3c01592}, year = {2023}, date = {2023-07-31}, journal = {Nano Letters}, volume = {23}, number = {15}, pages = {6979-6984}, abstract = {We demonstrate numerically how a spin wave (SW) beam obliquely incident on the edge of a thin film placed below a ferromagnetic stripe can excite leaky SWs guided along the stripe. During propagation, leaky waves emit energy back into the layer in the form of plane waves and several laterally shifted parallel SW beams. This resonance excitation, combined with interference effects of the reflected and re-emitted waves, results in the magnonic Wood’s anomaly and a significant increase of the Goos-Hänchen shift magnitude. This yields a unique platform to control SW reflection and transdimensional magnonic router that can transfer SWs from a 2D platform into a 1D guided mode.}, note = {PMID: 37523860}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We demonstrate numerically how a spin wave (SW) beam obliquely incident on the edge of a thin film placed below a ferromagnetic stripe can excite leaky SWs guided along the stripe. During propagation, leaky waves emit energy back into the layer in the form of plane waves and several laterally shifted parallel SW beams. This resonance excitation, combined with interference effects of the reflected and re-emitted waves, results in the magnonic Wood’s anomaly and a significant increase of the Goos-Hänchen shift magnitude. This yields a unique platform to control SW reflection and transdimensional magnonic router that can transfer SWs from a 2D platform into a 1D guided mode. Close https://doi.org/10.1021/acs.nanolett.3c01592 doi:10.1021/acs.nanolett.3c01592 Close
20.	Wojciech Śmigaj, Krzysztof Sobucki, Paweł Gruszecki, Maciej Krawczyk Modal approach to modeling spin wave scattering Phys. Rev. B, 108 , pp. 014418, 2023. Abstract \| Links \| BibTeX @article{PhysRevB.108.014418, title = {Modal approach to modeling spin wave scattering}, author = {Wojciech Śmigaj and Krzysztof Sobucki and Paweł Gruszecki and Maciej Krawczyk}, url = {https://link.aps.org/doi/10.1103/PhysRevB.108.014418}, doi = {10.1103/PhysRevB.108.014418}, year = {2023}, date = {2023-07-01}, journal = {Phys. Rev. B}, volume = {108}, pages = {014418}, publisher = {American Physical Society}, abstract = {Efficient numerical methods are required for the design of optimized devices. In magnonics, the primary computational tool is micromagnetic simulations, which solve the Landau-Lifshitz equation discretized in time and space. However, their computational cost is high, and the complexity of their output hinders insight into the physics of the simulated system, especially in the case of multimode propagating-wave-based devices. We propose a finite-element modal method allowing an efficient solution of the scattering problem for dipole-exchange spin waves propagating perpendicularly to the magnetization direction. The method gives direct access to the scattering matrix of the whole system and its components. We extend the formula for the power carried by a magnetostatic mode in the Damon-Eshbach configuration to the case with exchange, allowing the scattering coefficients to be normalized to represent the fraction of the input power transferred to each output channel. We apply the method to the analysis of spin wave scattering on a basic functional block of magnonic circuits, consisting of a resonator dynamically coupled to a thin film. The results and the method are validated by comparison with micromagnetic simulations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Efficient numerical methods are required for the design of optimized devices. In magnonics, the primary computational tool is micromagnetic simulations, which solve the Landau-Lifshitz equation discretized in time and space. However, their computational cost is high, and the complexity of their output hinders insight into the physics of the simulated system, especially in the case of multimode propagating-wave-based devices. We propose a finite-element modal method allowing an efficient solution of the scattering problem for dipole-exchange spin waves propagating perpendicularly to the magnetization direction. The method gives direct access to the scattering matrix of the whole system and its components. We extend the formula for the power carried by a magnetostatic mode in the Damon-Eshbach configuration to the case with exchange, allowing the scattering coefficients to be normalized to represent the fraction of the input power transferred to each output channel. We apply the method to the analysis of spin wave scattering on a basic functional block of magnonic circuits, consisting of a resonator dynamically coupled to a thin film. The results and the method are validated by comparison with micromagnetic simulations. Close https://link.aps.org/doi/10.1103/PhysRevB.108.014418 doi:10.1103/PhysRevB.108.014418 Close
19.	Jan Kisielewski, Paweł Gruszecki, Maciej Krawczyk, Vitalii Zablotskii, Andrzej Maziewski Between waves and patterns: Spin wave freezing in films with Dzyaloshinskii-Moriya interaction Phys. Rev. B, 107 , pp. 134416, 2023. Abstract \| Links \| BibTeX @article{PhysRevB.107.134416, title = {Between waves and patterns: Spin wave freezing in films with Dzyaloshinskii-Moriya interaction}, author = {Jan Kisielewski and Paweł Gruszecki and Maciej Krawczyk and Vitalii Zablotskii and Andrzej Maziewski}, url = {https://link.aps.org/doi/10.1103/PhysRevB.107.134416}, doi = {10.1103/PhysRevB.107.134416}, year = {2023}, date = {2023-04-12}, journal = {Phys. Rev. B}, volume = {107}, pages = {134416}, publisher = {American Physical Society}, abstract = {The relationship between waves and static pattern formation is an intriguing effect and remains unexplained in many areas of physics, including magnetism. We study the spin-wave-mediated spin reorientation transition (SRT) in magnetic films with uniaxial magnetic anisotropy and Dzyaloshinskii-Moriya interaction (DMI). In particular, we show that propagating spin waves can freeze in the SRT, causing periodic magnetic domains to arise, which is reminiscent of the wave amplitude distribution. This process can take place under the influence of a change in the magnetic field, but also of other parameters. Interestingly, at the SRT, DMI nonreciprocity leads to the emergence of flowing magnetization patterns, which suggests a spontaneous breaking of translational symmetry, and the formation of magnonic space-time crystals. The described phenomena are general and should take place in a large family of magnetic materials. Therefore, the results should be of great importance for the further development of spintronics and magnonics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The relationship between waves and static pattern formation is an intriguing effect and remains unexplained in many areas of physics, including magnetism. We study the spin-wave-mediated spin reorientation transition (SRT) in magnetic films with uniaxial magnetic anisotropy and Dzyaloshinskii-Moriya interaction (DMI). In particular, we show that propagating spin waves can freeze in the SRT, causing periodic magnetic domains to arise, which is reminiscent of the wave amplitude distribution. This process can take place under the influence of a change in the magnetic field, but also of other parameters. Interestingly, at the SRT, DMI nonreciprocity leads to the emergence of flowing magnetization patterns, which suggests a spontaneous breaking of translational symmetry, and the formation of magnonic space-time crystals. The described phenomena are general and should take place in a large family of magnetic materials. Therefore, the results should be of great importance for the further development of spintronics and magnonics. Close https://link.aps.org/doi/10.1103/PhysRevB.107.134416 doi:10.1103/PhysRevB.107.134416 Close
18.	Paweł Gruszecki, Jan Kisielewski Influence of Dzyaloshinskii–Moriya interaction and perpendicular anisotropy on spin waves propagation in stripe domain patterns and spin spirals Scientific Reports, 13 (1), pp. 1218, 2023, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{gruszecki_influence_2023, title = {Influence of Dzyaloshinskii–Moriya interaction and perpendicular anisotropy on spin waves propagation in stripe domain patterns and spin spirals}, author = {Paweł Gruszecki and Jan Kisielewski}, url = {https://www.nature.com/articles/s41598-023-28271-2}, doi = {10.1038/s41598-023-28271-2}, issn = {2045-2322}, year = {2023}, date = {2023-01-01}, urldate = {2023-01-25}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {1218}, abstract = {Texture-based magnonics focuses on the utilization of spin waves in magnetization textures to process information. Using micromagnetic simulations, we study how (1) the dynamic magnetic susceptibility, (2) dispersion relations, and (3) the equilibrium magnetic configurations in periodic magnetization textures in a ultrathin ferromagnetic film in remanence depend on the values of the Dzyaloshinskii–Moriya interaction and the perpendicular magnetocrystalline anisotropy. We observe that for large Dzyaloshinskii–Moriya interaction values, spin spirals with periods of tens of nanometers are the preferred state; for small Dzyaloshinskii–Moriya interaction values and large anisotropies, stripe domain patterns with over a thousand times larger period are preferable. We observe and explain the selectivity of the excitation of resonant modes by a linearly polarized microwave field. We study the propagation of spin waves along and perpendicular to the direction of the periodicity. For propagation along the direction of the periodicity, we observe a bandgap that closes and reopens, which is accompanied by a swap in the order of the bands. For waves propagating in the perpendicular direction, some modes can be used for unidirectional channeling of spin waves. Overall, our findings are promising in sensing and signal processing applications and explain the fundamental properties of periodic magnetization textures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Texture-based magnonics focuses on the utilization of spin waves in magnetization textures to process information. Using micromagnetic simulations, we study how (1) the dynamic magnetic susceptibility, (2) dispersion relations, and (3) the equilibrium magnetic configurations in periodic magnetization textures in a ultrathin ferromagnetic film in remanence depend on the values of the Dzyaloshinskii–Moriya interaction and the perpendicular magnetocrystalline anisotropy. We observe that for large Dzyaloshinskii–Moriya interaction values, spin spirals with periods of tens of nanometers are the preferred state; for small Dzyaloshinskii–Moriya interaction values and large anisotropies, stripe domain patterns with over a thousand times larger period are preferable. We observe and explain the selectivity of the excitation of resonant modes by a linearly polarized microwave field. We study the propagation of spin waves along and perpendicular to the direction of the periodicity. For propagation along the direction of the periodicity, we observe a bandgap that closes and reopens, which is accompanied by a swap in the order of the bands. For waves propagating in the perpendicular direction, some modes can be used for unidirectional channeling of spin waves. Overall, our findings are promising in sensing and signal processing applications and explain the fundamental properties of periodic magnetization textures. Close https://www.nature.com/articles/s41598-023-28271-2 doi:10.1038/s41598-023-28271-2 Close
2022
17.	Mateusz Zelent, Paweł Gruszecki, Mathieu Moalic, Olav Hellwig, Anjan Barman, Maciej Krawczyk Spin dynamics in patterned magnetic multilayers with perpendicular magnetic anisotropy Macedo, Rair (Ed.): 73 , pp. 1-51, Academic Press, 2022, ISSN: 0081-1947. Abstract \| Links \| BibTeX @incollection{ZELENT20221, title = {Spin dynamics in patterned magnetic multilayers with perpendicular magnetic anisotropy}, author = {Mateusz Zelent and Paweł Gruszecki and Mathieu Moalic and Olav Hellwig and Anjan Barman and Maciej Krawczyk}, editor = {Rair Macedo}, url = {https://www.sciencedirect.com/science/article/pii/S0081194722000029}, doi = {https://doi.org/10.1016/bs.ssp.2022.08.002}, issn = {0081-1947}, year = {2022}, date = {2022-10-27}, volume = {73}, pages = {1-51}, publisher = {Academic Press}, series = {Solid State Physics}, abstract = {The magnetization dynamics in nanostructures has been extensively studied in the last decades, and nanomagnetism has evolved significantly over that time, discovering new effects, developing numerous applications, and identifying promising new directions. This includes magnonics, an emerging research field oriented on the study of spin-wave dynamics and their applications. In this context, thin ferromagnetic films with perpendicular magnetic anisotropy (PMA) offer interesting opportunities to study spin waves, in particular, due to out-of-plane magnetization in remanence or at relatively weak external magnetic fields. This is the only magnetization configuration offering isotropic in-plane spin-wave propagation within the sample plane, the forward volume magnetostatic spin-wave geometry. The isotropic dispersion relation is highly important in designing signal-processing devices, offering superior prospects for direct replicating various concepts from photonics into magnonics. Analogous to photonic or phononic crystals, which are the building blocks of optoelectronics and phononics, magnonic crystals are considered as key components in magnonics applications. Arrays of nanodots and structured ferromagnetic thin films with a periodic array of holes, popularly known as antidot lattices based on PMA multilayers, have been recently studied. Novel magnonic properties related to propagating spin-wave modes, exploitation of the band gaps, and confined modes were demonstrated. Also, the existence of nontrivial magnonic band topologies has been shown. Moreover, the combination of PMA and Dzyaloshinskii–Moriya interaction leads to the formation of chiral magnetization states, including Néel domain walls, skyrmions, and skyrmionium states. This promotes the multilayers with PMA as an interesting topic for magnonics and this chapter reviews the background and attempts to provide future perspectives in this research field.}, keywords = {}, pubstate = {published}, tppubtype = {incollection} } Close The magnetization dynamics in nanostructures has been extensively studied in the last decades, and nanomagnetism has evolved significantly over that time, discovering new effects, developing numerous applications, and identifying promising new directions. This includes magnonics, an emerging research field oriented on the study of spin-wave dynamics and their applications. In this context, thin ferromagnetic films with perpendicular magnetic anisotropy (PMA) offer interesting opportunities to study spin waves, in particular, due to out-of-plane magnetization in remanence or at relatively weak external magnetic fields. This is the only magnetization configuration offering isotropic in-plane spin-wave propagation within the sample plane, the forward volume magnetostatic spin-wave geometry. The isotropic dispersion relation is highly important in designing signal-processing devices, offering superior prospects for direct replicating various concepts from photonics into magnonics. Analogous to photonic or phononic crystals, which are the building blocks of optoelectronics and phononics, magnonic crystals are considered as key components in magnonics applications. Arrays of nanodots and structured ferromagnetic thin films with a periodic array of holes, popularly known as antidot lattices based on PMA multilayers, have been recently studied. Novel magnonic properties related to propagating spin-wave modes, exploitation of the band gaps, and confined modes were demonstrated. Also, the existence of nontrivial magnonic band topologies has been shown. Moreover, the combination of PMA and Dzyaloshinskii–Moriya interaction leads to the formation of chiral magnetization states, including Néel domain walls, skyrmions, and skyrmionium states. This promotes the multilayers with PMA as an interesting topic for magnonics and this chapter reviews the background and attempts to provide future perspectives in this research field. Close https://www.sciencedirect.com/science/article/pii/S0081194722000029 doi:https://doi.org/10.1016/bs.ssp.2022.08.002 Close
16.	Katarzyna Kotus, Mathieu Moalic, Mateusz Zelent, Maciej Krawczyk, Paweł Gruszecki Scattering of spin waves in a multimode waveguide under the influence of confined magnetic skyrmion APL Materials, 10 (9), pp. 091101, 2022. Abstract \| Links \| BibTeX @article{doi:10.1063/5.0100594, title = {Scattering of spin waves in a multimode waveguide under the influence of confined magnetic skyrmion}, author = {Katarzyna Kotus and Mathieu Moalic and Mateusz Zelent and Maciej Krawczyk and Paweł Gruszecki}, url = {https://doi.org/10.1063/5.0100594}, doi = {10.1063/5.0100594}, year = {2022}, date = {2022-09-08}, journal = {APL Materials}, volume = {10}, number = {9}, pages = {091101}, abstract = {Nontrivial magnetization textures, such as skyrmions, have become a driving force in the physics of magnetism. Furthermore, the utilization of magnetization textures is fueling the development of magnon-based technologies that could provide beyond-CMOS solutions. Here, using a self-developed spin wave (SW) excitation scheme, we selectively excite specific modes and investigate the scattering of SWs on nanodot hosting a Néel-type skyrmion and placed above a multimode waveguide. In particular, at low frequencies, we observe significant reflections from the imprint induced by the skyrmion upon the waveguide. As the frequency increases, the transmission increases as well; however, it is accompanied by scattering to other types of modes. Here, we observe a direct contribution of the skyrmion to the scattering process and various types of conversions of the incident SW modes into other modes quantized by width for both reflected and transmitted SWs. The utilization of imprinted magnetization textures in nonplanar systems to control SW flow can open new possibilities for developing SW-based circuits for ultralow-power signal processing.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Nontrivial magnetization textures, such as skyrmions, have become a driving force in the physics of magnetism. Furthermore, the utilization of magnetization textures is fueling the development of magnon-based technologies that could provide beyond-CMOS solutions. Here, using a self-developed spin wave (SW) excitation scheme, we selectively excite specific modes and investigate the scattering of SWs on nanodot hosting a Néel-type skyrmion and placed above a multimode waveguide. In particular, at low frequencies, we observe significant reflections from the imprint induced by the skyrmion upon the waveguide. As the frequency increases, the transmission increases as well; however, it is accompanied by scattering to other types of modes. Here, we observe a direct contribution of the skyrmion to the scattering process and various types of conversions of the incident SW modes into other modes quantized by width for both reflected and transmitted SWs. The utilization of imprinted magnetization textures in nonplanar systems to control SW flow can open new possibilities for developing SW-based circuits for ultralow-power signal processing. Close https://doi.org/10.1063/5.0100594 doi:10.1063/5.0100594 Close
15.	Krzysztof Szulc, Silvia Tacchi, Aurelio Hierro-Rodríguez, Javier Díaz, Paweł Gruszecki, Piotr Graczyk, Carlos Quirós, Daniel Markó, José Ignacio Martín, María Vélez, David S Schmool, Giovanni Carlotti, Maciej Krawczyk, Luis Manuel Álvarez-Prado Reconfigurable Magnonic Crystals Based on Imprinted Magnetization Textures in Hard and Soft Dipolar-Coupled Bilayers ACS Nano, 0 (0), pp. 0, 2022, (PMID: 36043881). Abstract \| Links \| BibTeX @article{doi:10.1021/acsnano.2c04256, title = {Reconfigurable Magnonic Crystals Based on Imprinted Magnetization Textures in Hard and Soft Dipolar-Coupled Bilayers}, author = {Krzysztof Szulc and Silvia Tacchi and Aurelio Hierro-Rodríguez and Javier Díaz and Paweł Gruszecki and Piotr Graczyk and Carlos Quirós and Daniel Markó and José Ignacio Martín and María Vélez and David S Schmool and Giovanni Carlotti and Maciej Krawczyk and Luis Manuel Álvarez-Prado}, url = {https://doi.org/10.1021/acsnano.2c04256}, doi = {10.1021/acsnano.2c04256}, year = {2022}, date = {2022-08-31}, journal = {ACS Nano}, volume = {0}, number = {0}, pages = {0}, abstract = {Reconfigurable magnetization textures offer control of spin waves with promising properties for future low-power beyond-CMOS systems. However, materials with perpendicular magnetic anisotropy (PMA) suitable for stable magnetization-texture formation are characterized by high damping, which limits their applicability in magnonic devices. Here, we propose to overcome this limitation by using hybrid structures, i.e., a PMA layer magnetostatically coupled to a low-damping soft ferromagnetic film. We experimentally show that a periodic stripe-domain texture from a PMA layer is imprinted upon the soft layer and induces a nonreciprocal dispersion relation of the spin waves confined to the low-damping film. Moreover, an asymmetric bandgap features the spin-wave band diagram, which is a clear demonstration of collective spin-wave dynamics, a property characteristic for magnonic crystals with broken time-reversal symmetry. The composite character of the hybrid structure allows for stabilization of two magnetic states at remanence, with parallel and antiparallel orientation of net magnetization in hard and soft layers. The states can be switched using a low external magnetic field; therefore, the proposed system obtains an additional functionality of state reconfigurability. This study offers a link between reconfigurable magnetization textures and low-damping spin-wave dynamics, providing an opportunity to create miniaturized, programmable, and energy-efficient signal processing devices operating at high frequencies.}, note = {PMID: 36043881}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Reconfigurable magnetization textures offer control of spin waves with promising properties for future low-power beyond-CMOS systems. However, materials with perpendicular magnetic anisotropy (PMA) suitable for stable magnetization-texture formation are characterized by high damping, which limits their applicability in magnonic devices. Here, we propose to overcome this limitation by using hybrid structures, i.e., a PMA layer magnetostatically coupled to a low-damping soft ferromagnetic film. We experimentally show that a periodic stripe-domain texture from a PMA layer is imprinted upon the soft layer and induces a nonreciprocal dispersion relation of the spin waves confined to the low-damping film. Moreover, an asymmetric bandgap features the spin-wave band diagram, which is a clear demonstration of collective spin-wave dynamics, a property characteristic for magnonic crystals with broken time-reversal symmetry. The composite character of the hybrid structure allows for stabilization of two magnetic states at remanence, with parallel and antiparallel orientation of net magnetization in hard and soft layers. The states can be switched using a low external magnetic field; therefore, the proposed system obtains an additional functionality of state reconfigurability. This study offers a link between reconfigurable magnetization textures and low-damping spin-wave dynamics, providing an opportunity to create miniaturized, programmable, and energy-efficient signal processing devices operating at high frequencies. Close https://doi.org/10.1021/acsnano.2c04256 doi:10.1021/acsnano.2c04256 Close
14.	Mateusz Gołȩbiewski, Paweł Gruszecki, Maciej Krawczyk Self-Imaging of Spin Waves in Thin, Multimode Ferromagnetic Waveguides IEEE Transactions on Magnetics, 58 (8), pp. 1-5, 2022, ISSN: 1941-0069. Abstract \| Links \| BibTeX @article{9668947, title = {Self-Imaging of Spin Waves in Thin, Multimode Ferromagnetic Waveguides}, author = {Mateusz Gołȩbiewski and Paweł Gruszecki and Maciej Krawczyk}, doi = {10.1109/TMAG.2022.3140280}, issn = {1941-0069}, year = {2022}, date = {2022-08-01}, journal = {IEEE Transactions on Magnetics}, volume = {58}, number = {8}, pages = {1-5}, abstract = {Self-imaging of waves is an intriguing and spectacular effect. The phenomenon was first observed for light in 1836 by Henry Fox Talbot and to this day is the subject of research in many areas of physics, for various types of waves and in terms of different applications. This article is a Talbot-effect study for spin waves (SWs) in systems composed of a thin, ferromagnetic waveguide with a series of single-mode sources of SWs flowing into it. The proposed systems are studied with the use of micromagnetic simulations, and the SW self-imaging dependencies on many parameters are examined. We formulated conditions required for the formation of self-images and suitable for experimental realization. The results of the research form the basis for the further development of self-imaging-based magnonic devices.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Self-imaging of waves is an intriguing and spectacular effect. The phenomenon was first observed for light in 1836 by Henry Fox Talbot and to this day is the subject of research in many areas of physics, for various types of waves and in terms of different applications. This article is a Talbot-effect study for spin waves (SWs) in systems composed of a thin, ferromagnetic waveguide with a series of single-mode sources of SWs flowing into it. The proposed systems are studied with the use of micromagnetic simulations, and the SW self-imaging dependencies on many parameters are examined. We formulated conditions required for the formation of self-images and suitable for experimental realization. The results of the research form the basis for the further development of self-imaging-based magnonic devices. Close doi:10.1109/TMAG.2022.3140280 Close
13.	Mateusz Gołębiewski, Paweł Gruszecki, Maciej Krawczyk Self-Imaging Based Programmable Spin-Wave Lookup Tables Advanced Electronic Materials, n/a (n/a), pp. 2200373, 2022. Abstract \| Links \| BibTeX @article{https://doi.org/10.1002/aelm.202200373, title = {Self-Imaging Based Programmable Spin-Wave Lookup Tables}, author = {Mateusz Gołębiewski and Paweł Gruszecki and Maciej Krawczyk}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aelm.202200373}, doi = {https://doi.org/10.1002/aelm.202200373}, year = {2022}, date = {2022-07-21}, journal = {Advanced Electronic Materials}, volume = {n/a}, number = {n/a}, pages = {2200373}, abstract = {Abstract Inclusion of spin waves into the computing paradigm, where complementary metal-oxide-semiconductor devices are still at the fore, is now a challenge for scientists around the world. In this work, a wave phenomenon that has not yet been used in magnonics-self-imaging, also known as the Talbot effect, to design and simulate the operation of interference systems that perform logic functions on spin waves in thin ferromagnetic multimode waveguides is utilized. Lookup tables operating in this way are characterized by high programmability and scalability; thanks to which they are promising for their implementation in field-programmable gate arrays circuits, where multiple logic realizations can be obtained.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Abstract Inclusion of spin waves into the computing paradigm, where complementary metal-oxide-semiconductor devices are still at the fore, is now a challenge for scientists around the world. In this work, a wave phenomenon that has not yet been used in magnonics-self-imaging, also known as the Talbot effect, to design and simulate the operation of interference systems that perform logic functions on spin waves in thin ferromagnetic multimode waveguides is utilized. Lookup tables operating in this way are characterized by high programmability and scalability; thanks to which they are promising for their implementation in field-programmable gate arrays circuits, where multiple logic realizations can be obtained. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/aelm.202200373 doi:https://doi.org/10.1002/aelm.202200373 Close
12.	Paweł Gruszecki, Konstantin Y Guslienko, Igor L Lyubchanskii, Maciej Krawczyk Inelastic Spin-Wave Beam Scattering by Edge-Localized Spin Waves in a Ferromagnetic Thin Film Phys. Rev. Applied, 17 , pp. 044038, 2022. Abstract \| Links \| BibTeX @article{PhysRevApplied.17.044038, title = {Inelastic Spin-Wave Beam Scattering by Edge-Localized Spin Waves in a Ferromagnetic Thin Film}, author = {Paweł Gruszecki and Konstantin Y Guslienko and Igor L Lyubchanskii and Maciej Krawczyk}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.17.044038}, doi = {10.1103/PhysRevApplied.17.044038}, year = {2022}, date = {2022-04-20}, journal = {Phys. Rev. Applied}, volume = {17}, pages = {044038}, publisher = {American Physical Society}, abstract = {Spin waves are promising chargeless information carriers for the future, energetically efficient beyond CMOS systems. Among many advantages are the ease of achieving nonlinearity, the variety of possible interactions, and excitation types. Although the rapidly developing magnonic research has already yielded impressive realizations, multimode nonlinear effects, particularly with propagating waves and their nanoscale realizations, are still an open research problem.We theoretically study the dynamic interactions of spin waves confined to the edge of a thin ferromagnetic film with the spin-wave beam incident at this edge. We find inelastically scattered spin-wave beams at frequencies increased and decreased by the frequency of the edge spin-wave relative to the specularly reflected beam. We observe a strong dependence of the angular shift of the inelastic scattered spin-wave beam on the edge-mode frequency, which allows us to propose a magnonic demultiplexing of the signal encoded in spin waves propagating along the edge. Since dynamic magnetostatic interactions, which are ubiquitous in the spin-wave dynamics, are decisive in this process, this indicates the possibility of implementing the presented effects in other configurations and their use in magnonic systems.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spin waves are promising chargeless information carriers for the future, energetically efficient beyond CMOS systems. Among many advantages are the ease of achieving nonlinearity, the variety of possible interactions, and excitation types. Although the rapidly developing magnonic research has already yielded impressive realizations, multimode nonlinear effects, particularly with propagating waves and their nanoscale realizations, are still an open research problem.We theoretically study the dynamic interactions of spin waves confined to the edge of a thin ferromagnetic film with the spin-wave beam incident at this edge. We find inelastically scattered spin-wave beams at frequencies increased and decreased by the frequency of the edge spin-wave relative to the specularly reflected beam. We observe a strong dependence of the angular shift of the inelastic scattered spin-wave beam on the edge-mode frequency, which allows us to propose a magnonic demultiplexing of the signal encoded in spin waves propagating along the edge. Since dynamic magnetostatic interactions, which are ubiquitous in the spin-wave dynamics, are decisive in this process, this indicates the possibility of implementing the presented effects in other configurations and their use in magnonic systems. Close https://link.aps.org/doi/10.1103/PhysRevApplied.17.044038 doi:10.1103/PhysRevApplied.17.044038 Close
11.	A K Dhiman, R Gieniusz, Paweł Gruszecki, J Kisielewski, M Matczak, Z Kurant, I Sveklo, U Guzowska, M Tekielak, F Stobiecki, A Maziewski Magnetization statics and dynamics in (Ir/Co/Pt)6 multilayers with Dzyaloshinskii–Moriya interaction AIP Advances, 12 (4), pp. 045007, 2022. Abstract \| Links \| BibTeX @article{Dhiman2022DMI, title = {Magnetization statics and dynamics in (Ir/Co/Pt)6 multilayers with Dzyaloshinskii–Moriya interaction}, author = {A K Dhiman and R Gieniusz and Paweł Gruszecki and J Kisielewski and M Matczak and Z Kurant and I Sveklo and U Guzowska and M Tekielak and F Stobiecki and A Maziewski}, doi = {https://doi.org/10.1063/9.0000339}, year = {2022}, date = {2022-04-04}, urldate = {2022-04-04}, journal = {AIP Advances}, volume = {12}, number = {4}, pages = {045007}, abstract = {Magnetic multilayers of (Ir/Co/Pt)6 with interfacial Dzyaloshinskii-Moriya interaction (IDMI) were deposited by magnetron sputtering with Co thickness d=1.8 nm. Exploiting magneto-optical Kerr effect in longitudinal mode microscopy, magnetic force microscopy, and vibrating sample magnetometry, the magnetic field-driven evolution of domain structures and magnetization hysteresis loops have been studied. The existence of weak stripe domains structure was deduced – tens micrometers size domains with in-plane “core” magnetization modulated by hundred of nanometers domains with out-of-plane magnetization. Micromagnetic simulations interpreted such magnetization distribution. Quantitative evaluation of IDMI was carried out using Brillouin light scattering (BLS) spectroscopy as the difference between Stokes and anti-Stokes peak frequencies Δf. Due to the additive nature of IDMI, the asymmetric combination of Ir and Pt covers led to large values of effective IDMI energy density Deff. It was found that Stokes and anti-Stokes frequencies as well as Δf, measured as a function of in-plane applied magnetic field, show hysteresis. These results are explained under the consideration of the influence of IDMI on the dynamics of the in-plane magnetized “core” with weak stripe domains}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnetic multilayers of (Ir/Co/Pt)6 with interfacial Dzyaloshinskii-Moriya interaction (IDMI) were deposited by magnetron sputtering with Co thickness d=1.8 nm. Exploiting magneto-optical Kerr effect in longitudinal mode microscopy, magnetic force microscopy, and vibrating sample magnetometry, the magnetic field-driven evolution of domain structures and magnetization hysteresis loops have been studied. The existence of weak stripe domains structure was deduced – tens micrometers size domains with in-plane “core” magnetization modulated by hundred of nanometers domains with out-of-plane magnetization. Micromagnetic simulations interpreted such magnetization distribution. Quantitative evaluation of IDMI was carried out using Brillouin light scattering (BLS) spectroscopy as the difference between Stokes and anti-Stokes peak frequencies Δf. Due to the additive nature of IDMI, the asymmetric combination of Ir and Pt covers led to large values of effective IDMI energy density Deff. It was found that Stokes and anti-Stokes frequencies as well as Δf, measured as a function of in-plane applied magnetic field, show hysteresis. These results are explained under the consideration of the influence of IDMI on the dynamics of the in-plane magnetized “core” with weak stripe domains Close doi:https://doi.org/10.1063/9.0000339 Close
10.	A V Chumak, P Kabos, M Wu, C Abert, C Adelmann, A O Adeyeye, J Akerman, F G Aliev, A Anane, A Awad, C H Back, A Barman, G E W Bauer, M Becherer, E N Beginin, V A S V Bittencourt, Y M Blanter, P Bortolotti, I Boventer, D A Bozhko, S A Bunyaev, J J Carmiggelt, R R Cheenikundil, F Ciubotaru, S Cotofana, G Csaba, O V Dobrovolskiy, C Dubs, M Elyasi, K G Fripp, H Fulara, I A Golovchanskiy, C Gonzalez-Ballestero, Piotr Graczyk, D Grundler, Paweł Gruszecki, G Gubbiotti, K Guslienko, A Haldar, S Hamdioui, R Hertel, B Hillebrands, T Hioki, A Houshang, C -M Hu, H Huebl, M Huth, E Iacocca, M B Jungfleisch, G N Kakazei, A Khitun, R Khymyn, T Kikkawa, M Kloui, O Klein, Jarosław W. Kłos, S Knauer, S Koraltan, M Kostylev, Maciej Krawczyk, I N Krivorotov, V V Kruglyak, D Lachance-Quirion, S Ladak, R Lebrun, Y Li, M Lindner, R Macedo, S Mayr, G A Melkov, Szymon Mieszczak, Y Nakamura, H T Nembach, A A Nikitin, S A Nikitov, V Novosad, J A Otalora, Y Otani, A Papp, B Pigeau, P Pirro, W Porod, F Porrati, H Qin, Bivas Rana, T Reimann, F Riente, O Romero-Isart, A Ross, A V Sadovnikov, A R Safin, E Saitoh, G Schmidt, H Schultheiss, K Schultheiss, A A Serga, S Sharma, J M Shaw, D Suess, O Surzhenko, Krzysztof Szulc, T Taniguchi, M Urbanek, K Usami, A B Ustinov, T van der Sar, S van Dijken, V I Vasyuchka, R Verba, Viola S Kusminskiy, Q Wang, M Weides, M Weiler, S Wintz, S P Wolski, X Zhang Advances in Magnetics Roadmap on Spin-Wave Computing IEEE Trans. Magn., 58 (6), pp. 1-72, 2022, ISSN: 1941-0069. Abstract \| Links \| BibTeX @article{9706176, title = {Advances in Magnetics Roadmap on Spin-Wave Computing}, author = {A V Chumak and P Kabos and M Wu and C Abert and C Adelmann and A O Adeyeye and J Akerman and F G Aliev and A Anane and A Awad and C H Back and A Barman and G E W Bauer and M Becherer and E N Beginin and V A S V Bittencourt and Y M Blanter and P Bortolotti and I Boventer and D A Bozhko and S A Bunyaev and J J Carmiggelt and R R Cheenikundil and F Ciubotaru and S Cotofana and G Csaba and O V Dobrovolskiy and C Dubs and M Elyasi and K G Fripp and H Fulara and I A Golovchanskiy and C Gonzalez-Ballestero and Piotr Graczyk and D Grundler and Paweł Gruszecki and G Gubbiotti and K Guslienko and A Haldar and S Hamdioui and R Hertel and B Hillebrands and T Hioki and A Houshang and C -M Hu and H Huebl and M Huth and E Iacocca and M B Jungfleisch and G N Kakazei and A Khitun and R Khymyn and T Kikkawa and M Kloui and O Klein and Jarosław W. Kłos and S Knauer and S Koraltan and M Kostylev and Maciej Krawczyk and I N Krivorotov and V V Kruglyak and D Lachance-Quirion and S Ladak and R Lebrun and Y Li and M Lindner and R Macedo and S Mayr and G A Melkov and Szymon Mieszczak and Y Nakamura and H T Nembach and A A Nikitin and S A Nikitov and V Novosad and J A Otalora and Y Otani and A Papp and B Pigeau and P Pirro and W Porod and F Porrati and H Qin and Bivas Rana and T Reimann and F Riente and O Romero-Isart and A Ross and A V Sadovnikov and A R Safin and E Saitoh and G Schmidt and H Schultheiss and K Schultheiss and A A Serga and S Sharma and J M Shaw and D Suess and O Surzhenko and Krzysztof Szulc and T Taniguchi and M Urbanek and K Usami and A B Ustinov and T van der Sar and S van Dijken and V I Vasyuchka and R Verba and Viola S Kusminskiy and Q Wang and M Weides and M Weiler and S Wintz and S P Wolski and X Zhang}, doi = {10.1109/TMAG.2022.3149664}, issn = {1941-0069}, year = {2022}, date = {2022-02-07}, journal = {IEEE Trans. Magn.}, volume = {58}, number = {6}, pages = {1-72}, abstract = {Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in the GHz-to-THz frequency range, utilization of nonlinear and nonreciprocal phenomena, and compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scientific and technological challenges of the field are being extensively investigated, and many proof-of-concept prototypes have already been realized in laboratories. This roadmap is a product of the collective work of many authors, which covers versatile spin-wave computing approaches, conceptual building blocks, and underlying physical phenomena. In particular, the roadmap discusses the computation operations with the Boolean digital data, unconventional approaches, such as neuromorphic computing, and the progress toward magnon-based quantum computing. This article is organized as a collection of sub-sections grouped into seven large thematic sections. Each sub-section is prepared by one or a group of authors and concludes with a brief description of current challenges and the outlook of further development for each research direction.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Magnonics addresses the physical properties of spin waves and utilizes them for data processing. Scalability down to atomic dimensions, operation in the GHz-to-THz frequency range, utilization of nonlinear and nonreciprocal phenomena, and compatibility with CMOS are just a few of many advantages offered by magnons. Although magnonics is still primarily positioned in the academic domain, the scientific and technological challenges of the field are being extensively investigated, and many proof-of-concept prototypes have already been realized in laboratories. This roadmap is a product of the collective work of many authors, which covers versatile spin-wave computing approaches, conceptual building blocks, and underlying physical phenomena. In particular, the roadmap discusses the computation operations with the Boolean digital data, unconventional approaches, such as neuromorphic computing, and the progress toward magnon-based quantum computing. This article is organized as a collection of sub-sections grouped into seven large thematic sections. Each sub-section is prepared by one or a group of authors and concludes with a brief description of current challenges and the outlook of further development for each research direction. Close doi:10.1109/TMAG.2022.3149664 Close
9.	Krzysztof Sobucki, Paweł Gruszecki, Justyna Rychły, Maciej Krawczyk Control of the Phase of Reflected Spin Waves From Magnonic Gires–Tournois Interferometer of Subwavelength Width IEEE Transactions on Magnetics, 58 (2), pp. 1-5, 2022, ISSN: 1941-0069. Abstract \| Links \| BibTeX @article{9450803, title = {Control of the Phase of Reflected Spin Waves From Magnonic Gires–Tournois Interferometer of Subwavelength Width}, author = {Krzysztof Sobucki and Paweł Gruszecki and Justyna Rychły and Maciej Krawczyk}, doi = {10.1109/TMAG.2021.3088298}, issn = {1941-0069}, year = {2022}, date = {2022-01-20}, journal = {IEEE Transactions on Magnetics}, volume = {58}, number = {2}, pages = {1-5}, abstract = {The phase is one of the fundamental properties of a wave that allows to control interference effects and can be used to efficiently encode information. We examine numerically a magnonic resonator of the Gires–Tournois interferometer type, which enables the control of the phase of spin waves (SWs) reflected from the edge of the ferromagnetic film. The considered interferometer consists of a Py thin film and a thin, narrow Py stripe placed above its edge, both coupled magnetostatically. We show that the resonances and the phase of the reflected SWs are sensitive for a variation of the geometrical parameters of this bi-layered part of the system. The high sensitivity to film, stripe, and non-magnetic spacer thicknesses offers a prospect for developing magnonic metasurfaces and sensors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The phase is one of the fundamental properties of a wave that allows to control interference effects and can be used to efficiently encode information. We examine numerically a magnonic resonator of the Gires–Tournois interferometer type, which enables the control of the phase of spin waves (SWs) reflected from the edge of the ferromagnetic film. The considered interferometer consists of a Py thin film and a thin, narrow Py stripe placed above its edge, both coupled magnetostatically. We show that the resonances and the phase of the reflected SWs are sensitive for a variation of the geometrical parameters of this bi-layered part of the system. The high sensitivity to film, stripe, and non-magnetic spacer thicknesses offers a prospect for developing magnonic metasurfaces and sensors. Close doi:10.1109/TMAG.2021.3088298 Close
2021
8.	Michal Mruczkiewicz, Paweł Gruszecki The 2021 roadmap for noncollinear magnonics Solid State Physics, 2021, ISSN: 0081-1947. Abstract \| Links \| BibTeX @article{MRUCZKIEWICZ2021, title = {The 2021 roadmap for noncollinear magnonics}, author = {Michal Mruczkiewicz and Paweł Gruszecki}, url = {https://www.sciencedirect.com/science/article/pii/S0081194721000059}, doi = {https://doi.org/10.1016/bs.ssp.2021.09.001}, issn = {0081-1947}, year = {2021}, date = {2021-10-23}, journal = {Solid State Physics}, publisher = {Academic Press}, series = {Solid State Physics}, abstract = {Noncollinear magnonics is a rapidly developing topic of modern magnetism focusing on spin wave (magnon) dynamics in noncollinear spin textures. One of the driving forces of this research field is to employ nanosize dynamical noncollinear spin textures for the control and guiding of magnons. An unquestionable advantage of this approach is the potential to design programmable nanochannels with sizes below patterning limits. Furthermore, the noncollinear magnetic states induce nontrivial dynamical effects suitable for tailoring of SW propagation properties and emission of SWs. In the following, we will summarize the recent achievements of the field and discuss of current and future challenges.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Noncollinear magnonics is a rapidly developing topic of modern magnetism focusing on spin wave (magnon) dynamics in noncollinear spin textures. One of the driving forces of this research field is to employ nanosize dynamical noncollinear spin textures for the control and guiding of magnons. An unquestionable advantage of this approach is the potential to design programmable nanochannels with sizes below patterning limits. Furthermore, the noncollinear magnetic states induce nontrivial dynamical effects suitable for tailoring of SW propagation properties and emission of SWs. In the following, we will summarize the recent achievements of the field and discuss of current and future challenges. Close https://www.sciencedirect.com/science/article/pii/S0081194721000059 doi:https://doi.org/10.1016/bs.ssp.2021.09.001 Close
7.	Felix Groß, Mateusz Zelent, Ajay Gangwar, Sławomir Mamica, Paweł Gruszecki, Matthias Werner, Gisela Schütz, Markus Weigand, Eberhard J Goering, Christian H Back, Maciej Krawczyk, Joachim Gräfe Phase resolved observation of spin wave modes in antidot lattices Appl. Phys. Lett., 118 (23), pp. 232403, 2021. Abstract \| Links \| BibTeX @article{doi:10.1063/5.0045142, title = {Phase resolved observation of spin wave modes in antidot lattices}, author = {Felix Groß and Mateusz Zelent and Ajay Gangwar and Sławomir Mamica and Paweł Gruszecki and Matthias Werner and Gisela Schütz and Markus Weigand and Eberhard J Goering and Christian H Back and Maciej Krawczyk and Joachim Gräfe}, url = {https://doi.org/10.1063/5.0045142}, doi = {10.1063/5.0045142}, year = {2021}, date = {2021-06-10}, journal = {Appl. Phys. Lett.}, volume = {118}, number = {23}, pages = {232403}, abstract = {Antidot lattices have proven to be a powerful tool for spin wave band structure manipulation. Utilizing time-resolved scanning transmission x-ray microscopy, we are able to experimentally image edge-localized spin wave modes in an antidot lattice with a lateral confinement down to <80nm x 130 nm. At higher frequencies, spin wave dragonfly patterns formed by the demagnetizing structures of the antidot lattice are excited. Evaluating their relative phase with respect to the propagating mode within the antidot channel reveals that the dragonfly modes are not directly excited by the antenna but need the propagating mode as an energy mediator. Furthermore, micromagnetic simulations reveal that additional dispersion branches exist for a tilted external field geometry. These branches correspond to asymmetric spin wave modes that cannot be excited in a non-tilted field geometry due to the symmetry restriction. In addition to the band having a negative slope, these asymmetric modes also cause an unexpected transformation of the band structure, slightly reaching into the otherwise empty bandgap between the low frequency edge modes and the fundamental mode. The presented phase resolved investigation of spin waves is a crucial step for spin wave manipulation in magnonic crystals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Antidot lattices have proven to be a powerful tool for spin wave band structure manipulation. Utilizing time-resolved scanning transmission x-ray microscopy, we are able to experimentally image edge-localized spin wave modes in an antidot lattice with a lateral confinement down to <80nm x 130 nm. At higher frequencies, spin wave dragonfly patterns formed by the demagnetizing structures of the antidot lattice are excited. Evaluating their relative phase with respect to the propagating mode within the antidot channel reveals that the dragonfly modes are not directly excited by the antenna but need the propagating mode as an energy mediator. Furthermore, micromagnetic simulations reveal that additional dispersion branches exist for a tilted external field geometry. These branches correspond to asymmetric spin wave modes that cannot be excited in a non-tilted field geometry due to the symmetry restriction. In addition to the band having a negative slope, these asymmetric modes also cause an unexpected transformation of the band structure, slightly reaching into the otherwise empty bandgap between the low frequency edge modes and the fundamental mode. The presented phase resolved investigation of spin waves is a crucial step for spin wave manipulation in magnonic crystals. Close https://doi.org/10.1063/5.0045142 doi:10.1063/5.0045142 Close
6.	Krzysztof Sobucki, Wojciech Śmigaj, Justyna Rychły, Maciej Krawczyk, Paweł Gruszecki Resonant subwavelength control of the phase of spin waves reflected from a Gires–Tournois interferometer Sci. Rep., 11 (1), pp. 4428, 2021, ISSN: 2045-2322. Abstract \| Links \| BibTeX @article{sobucki_resonant_2021, title = {Resonant subwavelength control of the phase of spin waves reflected from a Gires–Tournois interferometer}, author = {Krzysztof Sobucki and Wojciech Śmigaj and Justyna Rychły and Maciej Krawczyk and Paweł Gruszecki}, url = {https://www.nature.com/articles/s41598-021-83307-9}, doi = {10.1038/s41598-021-83307-9}, issn = {2045-2322}, year = {2021}, date = {2021-02-24}, urldate = {2021-02-25}, journal = {Sci. Rep.}, volume = {11}, number = {1}, pages = {4428}, abstract = {Subwavelength resonant elements are essential building blocks of metamaterials and metasurfaces, which have revolutionized photonics. Despite similarities between different wave phenomena, other types of interactions can make subwavelength coupling significantly distinct; its investigation in their context is therefore of interest both from the physics and applications perspective. In this work, we demonstrate a fully magnonic Gires–Tournois interferometer based on a subwavelength resonator made of a narrow ferromagnetic stripe lying above the edge of a ferromagnetic film. The bilayer formed by the stripe and the film underneath supports two propagative spin-wave modes, one strongly coupled with spin waves propagating in the rest of the film and another almost completely reflected at the ends of the bilayer. When the Fabry–Perot resonance conditions for this mode are satisfied, the weak coupling between both modes is sufficient to achieve high sensitivity of the phase of waves reflected from the resonator to the stripe width and, more interestingly, also to the stripe-film separation. Such spin-wave phase manipulation capabilities are a prerequisite for the design of spin-wave metasurfaces and may stimulate development of magnonic logic devices and sensors detecting magnetic nanoparticles.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Subwavelength resonant elements are essential building blocks of metamaterials and metasurfaces, which have revolutionized photonics. Despite similarities between different wave phenomena, other types of interactions can make subwavelength coupling significantly distinct; its investigation in their context is therefore of interest both from the physics and applications perspective. In this work, we demonstrate a fully magnonic Gires–Tournois interferometer based on a subwavelength resonator made of a narrow ferromagnetic stripe lying above the edge of a ferromagnetic film. The bilayer formed by the stripe and the film underneath supports two propagative spin-wave modes, one strongly coupled with spin waves propagating in the rest of the film and another almost completely reflected at the ends of the bilayer. When the Fabry–Perot resonance conditions for this mode are satisfied, the weak coupling between both modes is sufficient to achieve high sensitivity of the phase of waves reflected from the resonator to the stripe width and, more interestingly, also to the stripe-film separation. Such spin-wave phase manipulation capabilities are a prerequisite for the design of spin-wave metasurfaces and may stimulate development of magnonic logic devices and sensors detecting magnetic nanoparticles. Close https://www.nature.com/articles/s41598-021-83307-9 doi:10.1038/s41598-021-83307-9 Close
5.	Paweł Gruszecki, Igor L. Lyubchanskii, Konstantin Y Guslienko, Maciej Krawczyk Local non-linear excitation of sub-100 nm bulk-type spin waves by edge-localized spin waves in magnetic films Appl. Phys. Lett., 118 (6), pp. 062408, 2021. Abstract \| Links \| BibTeX @article{doi:10.1063/5.0041030, title = {Local non-linear excitation of sub-100 nm bulk-type spin waves by edge-localized spin waves in magnetic films}, author = {Paweł Gruszecki and Igor L. Lyubchanskii and Konstantin Y Guslienko and Maciej Krawczyk}, doi = {10.1063/5.0041030}, year = {2021}, date = {2021-02-11}, journal = {Appl. Phys. Lett.}, volume = {118}, number = {6}, pages = {062408}, abstract = {The excitation of high-frequency short-wavelength spin waves is a challenge limiting the application of these propagating magnetization disturbances in information processing systems. We propose a method of local excitation of the high-frequency spin waves using the non-linear nature of magnetization dynamics. We demonstrate with numeric simulations that an edge-localized spin wave can be used to excite plane waves propagating obliquely from the film's edge at a doubled frequency and over twice shorter in wavelength. The excitation mechanism is a direct result of the ellipticity of the magnetic moment precession that is related to the edge-mode propagation. As a consequence, the magnetization component tangential to the equilibrium orientation oscillates with doubled temporal and spatial frequencies, which leads to efficient excitation of the plane spin waves. The threshold-less non-linear process of short-wavelength spin-wave excitation proposed in our study is promising for integration with an inductive or point-like spin-torque source of edge spin waves. The research leading to these results received funding from the National Science Centre of Poland, Project No. 2019/35/D/ST3/03729. I.L.L. acknowledges support from a COST action under Project No. CA17123 MAGNETOFON. K.Y.G. acknowledges support from IKERBASQUE (the Basque Foundation for Science) and from the Spanish Ministerio de Ciencia, Innovacion y Universidades Grant No. PID2019-108075RB-C33/AEI/10.13039/501100011033. The simulations were partially performed at the Poznan Supercomputing and Networking Center (Grant No. 398).}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The excitation of high-frequency short-wavelength spin waves is a challenge limiting the application of these propagating magnetization disturbances in information processing systems. We propose a method of local excitation of the high-frequency spin waves using the non-linear nature of magnetization dynamics. We demonstrate with numeric simulations that an edge-localized spin wave can be used to excite plane waves propagating obliquely from the film's edge at a doubled frequency and over twice shorter in wavelength. The excitation mechanism is a direct result of the ellipticity of the magnetic moment precession that is related to the edge-mode propagation. As a consequence, the magnetization component tangential to the equilibrium orientation oscillates with doubled temporal and spatial frequencies, which leads to efficient excitation of the plane spin waves. The threshold-less non-linear process of short-wavelength spin-wave excitation proposed in our study is promising for integration with an inductive or point-like spin-torque source of edge spin waves. The research leading to these results received funding from the National Science Centre of Poland, Project No. 2019/35/D/ST3/03729. I.L.L. acknowledges support from a COST action under Project No. CA17123 MAGNETOFON. K.Y.G. acknowledges support from IKERBASQUE (the Basque Foundation for Science) and from the Spanish Ministerio de Ciencia, Innovacion y Universidades Grant No. PID2019-108075RB-C33/AEI/10.13039/501100011033. The simulations were partially performed at the Poznan Supercomputing and Networking Center (Grant No. 398). Close doi:10.1063/5.0041030 Close
4.	Jarosław W. Kłos, Igor L. Lyubchanskii, Maciej Krawczyk, Paweł Gruszecki, Szymon Mieszczak, Justyna Rychły, Yuliya S. Dadoenkova, Nataliya N. Dadoenkova Magnonics and Confinement of Light in Photonic–Magnonic Crystals, in Optomagnonic Structures Almpanis, Evangelos (Ed.): Chapter 2, pp. 79–134, World Scientific Publishing, Singapure, 2021, ISBN: 978-981-122-005-0. Abstract \| Links \| BibTeX @inbook{opto-mag, title = {Magnonics and Confinement of Light in Photonic–Magnonic Crystals, in Optomagnonic Structures}, author = {Jarosław W. Kłos and Igor L. Lyubchanskii and Maciej Krawczyk and Paweł Gruszecki and Szymon Mieszczak and Justyna Rychły and Yuliya S. Dadoenkova and Nataliya N. Dadoenkova}, editor = {Evangelos Almpanis}, doi = {10.1142/9789811220050_0002}, isbn = {978-981-122-005-0}, year = {2021}, date = {2021-02-08}, pages = {79–134}, publisher = {World Scientific Publishing}, address = {Singapure}, chapter = {2}, abstract = {We discuss the spin-wave confinement in the magnetic components of magnetophotonic structures. In the initial sections of the chapter, we describe the principles of magnetization dynamics, including both the exchange and dipolar interactions. We showed that the spin-wave spectrum in confined geometry is determined not only by the spatial constraints but is also strongly influenced by non-local demagnetizing effects. In addition, we analyze the localization of light in the regions of spin-wave confinement, which can strengthen the magneto–optical interaction. Such enhancement can be potentially realized in photonic–magnonic crystals, where the light localization in magnetic components of the structure results from the periodicity and the spin waves co-exist with electromagnetic waves. The final sections are devoted to the Faraday effect and Goos–Hänchen effect in photonic–magnonic crystals.}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } Close We discuss the spin-wave confinement in the magnetic components of magnetophotonic structures. In the initial sections of the chapter, we describe the principles of magnetization dynamics, including both the exchange and dipolar interactions. We showed that the spin-wave spectrum in confined geometry is determined not only by the spatial constraints but is also strongly influenced by non-local demagnetizing effects. In addition, we analyze the localization of light in the regions of spin-wave confinement, which can strengthen the magneto–optical interaction. Such enhancement can be potentially realized in photonic–magnonic crystals, where the light localization in magnetic components of the structure results from the periodicity and the spin waves co-exist with electromagnetic waves. The final sections are devoted to the Faraday effect and Goos–Hänchen effect in photonic–magnonic crystals. Close doi:10.1142/9789811220050_0002 Close
3.	Nick Träger, Paweł Gruszecki, Filip Lisiecki, Felix Groß, Johannes Förster, Markus Weigand, Hubert Głowiński, Piotr Kuświk, Janusz Dubowik, Gisela Schütz, Maciej Krawczyk, Joachim Gräfe Real-Space Observation of Magnon Interaction with Driven Space-Time Crystals Phys. Rev. Lett., 126 , pp. 057201, 2021. Abstract \| Links \| BibTeX @article{PhysRevLett.126.057201, title = {Real-Space Observation of Magnon Interaction with Driven Space-Time Crystals}, author = {Nick Träger and Paweł Gruszecki and Filip Lisiecki and Felix Groß and Johannes Förster and Markus Weigand and Hubert Głowiński and Piotr Kuświk and Janusz Dubowik and Gisela Schütz and Maciej Krawczyk and Joachim Gräfe}, url = {https://doi.org/10.1103/PhysRevLett.126.057201}, doi = {10.1103/PhysRevLett.126.057201}, year = {2021}, date = {2021-02-03}, journal = {Phys. Rev. Lett.}, volume = {126}, pages = {057201}, abstract = {The concept of space-time crystals (STC), i.e., translational symmetry breaking in time and space, was recently proposed and experimentally demonstrated for quantum systems. Here, we transfer this concept to magnons and experimentally demonstrate a driven STC at room temperature. The STC is realized by strong homogeneous microwave pumping of a micron-sized permalloy (Py) stripe and is directly imaged by scanning transmission x-ray microscopy (STXM). For a fundamental understanding of the formation of the STC, micromagnetic simulations are carefully adapted to model the experimental findings. Beyond the mere generation of a STC, we observe the formation of a magnonic band structure due to back folding of modes at the STC’s Brillouin zone boundaries. We show interactions of magnons with the STC that appear as lattice scattering, which results in the generation of ultrashort spin waves (SW) down to 100-nm wavelengths that cannot be described by classical dispersion relations for linear SW excitation. We expect that room-temperature STCs will be useful to investigate nonlinear wave physics, as they can be easily generated and manipulated to control their spatial and temporal band structures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The concept of space-time crystals (STC), i.e., translational symmetry breaking in time and space, was recently proposed and experimentally demonstrated for quantum systems. Here, we transfer this concept to magnons and experimentally demonstrate a driven STC at room temperature. The STC is realized by strong homogeneous microwave pumping of a micron-sized permalloy (Py) stripe and is directly imaged by scanning transmission x-ray microscopy (STXM). For a fundamental understanding of the formation of the STC, micromagnetic simulations are carefully adapted to model the experimental findings. Beyond the mere generation of a STC, we observe the formation of a magnonic band structure due to back folding of modes at the STC’s Brillouin zone boundaries. We show interactions of magnons with the STC that appear as lattice scattering, which results in the generation of ultrashort spin waves (SW) down to 100-nm wavelengths that cannot be described by classical dispersion relations for linear SW excitation. We expect that room-temperature STCs will be useful to investigate nonlinear wave physics, as they can be easily generated and manipulated to control their spatial and temporal band structures. Close https://doi.org/10.1103/PhysRevLett.126.057201 doi:10.1103/PhysRevLett.126.057201 Close
2.	Nick Träger, Filip Lisiecki, Robert Lawitzki, Markus Weigand, Hubert Głowiński, Gisela Schütz, Guido Schmitz, Piotr Kuświk, Maciej Krawczyk, Joachim Gräfe, Paweł Gruszecki Competing spin wave emission mechanisms revealed by time-resolved x-ray microscopy Phys. Rev. B, 103 , pp. 014430, 2021. Abstract \| Links \| BibTeX @article{PhysRevB.103.014430, title = {Competing spin wave emission mechanisms revealed by time-resolved x-ray microscopy}, author = {Nick Träger and Filip Lisiecki and Robert Lawitzki and Markus Weigand and Hubert Głowiński and Gisela Schütz and Guido Schmitz and Piotr Kuświk and Maciej Krawczyk and Joachim Gräfe and Paweł Gruszecki}, url = {https://link.aps.org/doi/10.1103/PhysRevB.103.014430}, doi = {10.1103/PhysRevB.103.014430}, year = {2021}, date = {2021-01-19}, journal = {Phys. Rev. B}, volume = {103}, pages = {014430}, publisher = {American Physical Society}, abstract = {Spin wave emission and propagation in magnonic waveguides represent a highly promising alternative for beyond-CMOS computing. It is therefore all the more important to fully understand the underlying physics of the emission process. Here, we use time-resolved scanning transmission x-ray microscopy to directly image the formation process of the globally excited local emission of spin waves in a permalloy waveguide at the nanoscale. Thereby, we observe spin wave emission from the corner of the waveguide as well as from a local oscillation of a domain-wall-like structure within the waveguide. Additionally, an isofrequency contour analysis is used to fully explain the origin of quasicylindrical spin wave excitation from the corner and its concurrent nonreflection and nonrefraction at the domain interface. This study is complemented by micromagnetic simulations which perfectly fit the experimental findings. Thus, we clarify the fundamental question of the emission mechanisms in magnonic waveguides which lay the basis for future magnonic operations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spin wave emission and propagation in magnonic waveguides represent a highly promising alternative for beyond-CMOS computing. It is therefore all the more important to fully understand the underlying physics of the emission process. Here, we use time-resolved scanning transmission x-ray microscopy to directly image the formation process of the globally excited local emission of spin waves in a permalloy waveguide at the nanoscale. Thereby, we observe spin wave emission from the corner of the waveguide as well as from a local oscillation of a domain-wall-like structure within the waveguide. Additionally, an isofrequency contour analysis is used to fully explain the origin of quasicylindrical spin wave excitation from the corner and its concurrent nonreflection and nonrefraction at the domain interface. This study is complemented by micromagnetic simulations which perfectly fit the experimental findings. Thus, we clarify the fundamental question of the emission mechanisms in magnonic waveguides which lay the basis for future magnonic operations. Close https://link.aps.org/doi/10.1103/PhysRevB.103.014430 doi:10.1103/PhysRevB.103.014430 Close
2020
1.	Szymon Mieszczak, Oksana Busel, Paweł Gruszecki, Andriy N Kuchko, Jarosław W. Kłos, Maciej Krawczyk Anomalous Refraction of Spin Waves as a Way to Guide Signals in Curved Magnonic Multimode Waveguides Physical Review Applied, 13 (5), pp. 054038, 2020, ISSN: 2331-7019. Abstract \| Links \| BibTeX @article{mieszczak_anomalous_2020, title = {Anomalous Refraction of Spin Waves as a Way to Guide Signals in Curved Magnonic Multimode Waveguides}, author = {Szymon Mieszczak and Oksana Busel and Paweł Gruszecki and Andriy N Kuchko and Jarosław W. Kłos and Maciej Krawczyk}, url = {https://link.aps.org/doi/10.1103/PhysRevApplied.13.054038}, doi = {10.1103/PhysRevApplied.13.054038}, issn = {2331-7019}, year = {2020}, date = {2020-01-01}, urldate = {2021-05-04}, journal = {Physical Review Applied}, volume = {13}, number = {5}, pages = {054038}, abstract = {We present a method for efficient spin-wave guiding within the magnonic nanostructures. Our technique is based on the anomalous refraction in the metamaterial flat slab. The gradual change of the material parameters (saturation magnetization or magnetic anisotropy) across the slab allows tilting the wavefronts of the transmitted spin waves and controlling the refraction. Numerical studies of the spin-wave refraction are preceded by the analytical calculations of the phase shift acquired by the spin wave due to the change of material parameters in a confined area. We demonstrate that our findings can be used to guide the spin waves smoothly in curved waveguides, even through sharp bends, without reflection and scattering between different waveguide’s modes, preserving the phase, the quantity essential for wave computing.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We present a method for efficient spin-wave guiding within the magnonic nanostructures. Our technique is based on the anomalous refraction in the metamaterial flat slab. The gradual change of the material parameters (saturation magnetization or magnetic anisotropy) across the slab allows tilting the wavefronts of the transmitted spin waves and controlling the refraction. Numerical studies of the spin-wave refraction are preceded by the analytical calculations of the phase shift acquired by the spin wave due to the change of material parameters in a confined area. We demonstrate that our findings can be used to guide the spin waves smoothly in curved waveguides, even through sharp bends, without reflection and scattering between different waveguide’s modes, preserving the phase, the quantity essential for wave computing. Close https://link.aps.org/doi/10.1103/PhysRevApplied.13.054038 doi:10.1103/PhysRevApplied.13.054038 Close