M.Sc. Mathieu Moalic
- Tel: +48 61 829 5254
- Loc: wing G, second floor, room 191
- Email: matmoa@amu.edu.pl
- URL: https://github.com/MathieuMoalic
Scientific degrees
MSc in physics – 2020
BSc in physics – 2018
Research interests
Keywords: magnonics, numerical simulations, spintronics, magnetization dynamics
My research is focused on the static and dynamic study of micromagnetic systems such as coupled skyrmions, spin wave generations, antidot lattices. To achieve it, I develop my own post processing and simulation software as well as using MuMax3.
Publications
2024 |
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8. | Mathieu Moalic, Mateusz Zelent, Krzysztof Szulc, Maciej Krawczyk The role of non-uniform magnetization texture for magnon–magnon coupling in an antidot lattice Scientific Reports, 14 (1), pp. 11501, 2024, ISSN: 2045-2322. @article{moalic_role_2024, title = {The role of non-uniform magnetization texture for magnon–magnon coupling in an antidot lattice}, author = {Mathieu Moalic and Mateusz Zelent and Krzysztof Szulc and Maciej Krawczyk}, url = {https://www.nature.com/articles/s41598-024-61246-5}, doi = {10.1038/s41598-024-61246-5}, issn = {2045-2322}, year = {2024}, date = {2024-05-20}, urldate = {2024-05-23}, journal = {Scientific Reports}, volume = {14}, number = {1}, pages = {11501}, abstract = {We numerically study the spin-wave dynamics in an antidot lattice based on a Co/Pd multilayer structure with reduced perpendicular magnetic anisotropy at the edges of the antidots. This structure forms a magnonic crystal with a periodic antidot pattern and a periodic magnetization configuration consisting of out-of-plane magnetized bulk and in-plane magnetized rims. Our results show a different behavior of spin waves in the bulk and in the rims under varying out-of-plane external magnetic field strength, revealing complex spin-wave spectra and hybridizations between the modes of these two subsystems. A particularly strong magnon–magnon coupling, due to exchange interactions, is found between the fundamental bulk spin-wave mode and the second-order radial rim modes. However, the dynamical coupling between the spin-wave modes at low frequencies, involving the first-order radial rim modes, is masked by the changes in the static magnetization at the bulk–rim interface with magnetic field changes. The study expands the horizons of magnonic-crystal research by combining periodic structural patterning and non-collinear magnetization texture to achieve strong magnon–magnon coupling, highlighting the significant role of exchange interactions in the hybridization.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We numerically study the spin-wave dynamics in an antidot lattice based on a Co/Pd multilayer structure with reduced perpendicular magnetic anisotropy at the edges of the antidots. This structure forms a magnonic crystal with a periodic antidot pattern and a periodic magnetization configuration consisting of out-of-plane magnetized bulk and in-plane magnetized rims. Our results show a different behavior of spin waves in the bulk and in the rims under varying out-of-plane external magnetic field strength, revealing complex spin-wave spectra and hybridizations between the modes of these two subsystems. A particularly strong magnon–magnon coupling, due to exchange interactions, is found between the fundamental bulk spin-wave mode and the second-order radial rim modes. However, the dynamical coupling between the spin-wave modes at low frequencies, involving the first-order radial rim modes, is masked by the changes in the static magnetization at the bulk–rim interface with magnetic field changes. The study expands the horizons of magnonic-crystal research by combining periodic structural patterning and non-collinear magnetization texture to achieve strong magnon–magnon coupling, highlighting the significant role of exchange interactions in the hybridization. |
2023 |
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7. | Gauthier Philippe, Mathieu Moalic, Jarosław W. Kłos Unidirectional spin wave emission by traveling pair of magnetic field profiles Journal of Magnetism and Magnetic Materials, 587 , pp. 171359, 2023, ISSN: 0304-8853. @article{PHILIPPE2023171359, title = {Unidirectional spin wave emission by traveling pair of magnetic field profiles}, author = {Gauthier Philippe and Mathieu Moalic and Jarosław W. Kłos}, url = {https://www.sciencedirect.com/science/article/pii/S0304885323010090}, doi = {https://doi.org/10.1016/j.jmmm.2023.171359}, issn = {0304-8853}, year = {2023}, date = {2023-10-11}, journal = {Journal of Magnetism and Magnetic Materials}, volume = {587}, pages = {171359}, abstract = {We demonstrate that the spin wave Cherenkov effect can be used to design the unidirectional spin wave emitter with tunable frequency and switchable direction of emission. In our numerical studies, we propose to use a pair of traveling profiles of the magnetic field which generate the spin waves, for sufficiently large velocity of their motion. In the considered system, the spin waves of shorter (longer) wavelengths are induced at the front (back) of the moving profiles and interfere constructively or destructively, depending on the velocity of the profiles. Moreover, we showed that the spin waves can be confined between the pair of traveling profiles of the magnetic field. This work opens the perspectives for the experimental studies in hybrid magnonic-superconducting systems where the magnetic vortices in a superconductor can be used as moving sources of the magnetic field driving the spin waves in the ferromagnetic subsystem.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We demonstrate that the spin wave Cherenkov effect can be used to design the unidirectional spin wave emitter with tunable frequency and switchable direction of emission. In our numerical studies, we propose to use a pair of traveling profiles of the magnetic field which generate the spin waves, for sufficiently large velocity of their motion. In the considered system, the spin waves of shorter (longer) wavelengths are induced at the front (back) of the moving profiles and interfere constructively or destructively, depending on the velocity of the profiles. Moreover, we showed that the spin waves can be confined between the pair of traveling profiles of the magnetic field. This work opens the perspectives for the experimental studies in hybrid magnonic-superconducting systems where the magnetic vortices in a superconductor can be used as moving sources of the magnetic field driving the spin waves in the ferromagnetic subsystem. |
6. | Mateusz Zelent, Mathieu Moalic, Michal Mruczkiewicz, Xiaoguang Li, Yan Zhou, Maciej Krawczyk Stabilization and racetrack application of asymmetric Néel skyrmions in hybrid nanostructures Scientific Reports, 13 (1), pp. 13572, 2023, ISSN: 2045-2322. @article{zelent_stabilization_2023, title = {Stabilization and racetrack application of asymmetric Néel skyrmions in hybrid nanostructures}, author = {Mateusz Zelent and Mathieu Moalic and Michal Mruczkiewicz and Xiaoguang Li and Yan Zhou and Maciej Krawczyk}, url = {https://www.nature.com/articles/s41598-023-40236-z}, doi = {10.1038/s41598-023-40236-z}, issn = {2045-2322}, year = {2023}, date = {2023-08-21}, urldate = {2023-08-24}, journal = {Scientific Reports}, volume = {13}, number = {1}, pages = {13572}, abstract = {Magnetic skyrmions, topological quasiparticles, are small stable magnetic textures that possess intriguing properties and potential for data storage applications. Hybrid nanostructures comprised of skyrmions and soft magnetic material can offer additional advantages for developing skyrmion-based spintronic and magnonic devices. We show that a Néel-type skyrmion confined within a nanodot placed on top of a ferromagnetic in-plane magnetized stripe produces a unique and compelling platform for exploring the mutual coupling between magnetization textures. The skyrmion induces an imprint upon the stripe, which, in turn, asymmetrically squeezes the skyrmion in the dot, increasing their size and the range of skyrmion stability at small values of Dzyaloshinskii–Moriya interaction, as well as introducing skyrmion bi-stability. Finally, by exploiting the properties of the skyrmion in a hybrid system, we demonstrate unlimited skyrmion transport along a racetrack, free of the skyrmion Hall effect.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Magnetic skyrmions, topological quasiparticles, are small stable magnetic textures that possess intriguing properties and potential for data storage applications. Hybrid nanostructures comprised of skyrmions and soft magnetic material can offer additional advantages for developing skyrmion-based spintronic and magnonic devices. We show that a Néel-type skyrmion confined within a nanodot placed on top of a ferromagnetic in-plane magnetized stripe produces a unique and compelling platform for exploring the mutual coupling between magnetization textures. The skyrmion induces an imprint upon the stripe, which, in turn, asymmetrically squeezes the skyrmion in the dot, increasing their size and the range of skyrmion stability at small values of Dzyaloshinskii–Moriya interaction, as well as introducing skyrmion bi-stability. Finally, by exploiting the properties of the skyrmion in a hybrid system, we demonstrate unlimited skyrmion transport along a racetrack, free of the skyrmion Hall effect. |
5. | Uladzislau Makartsou, Mathieu Moalic, Mateusz Zelent, Michal Mruczkiewicz, Maciej Krawczyk Control of vortex chirality in a symmetric ferromagnetic ring using a ferromagnetic nanoelement Nanoscale, pp. -, 2023. @article{D3NR00582H, title = {Control of vortex chirality in a symmetric ferromagnetic ring using a ferromagnetic nanoelement}, author = {Uladzislau Makartsou and Mathieu Moalic and Mateusz Zelent and Michal Mruczkiewicz and Maciej Krawczyk}, url = {http://dx.doi.org/10.1039/D3NR00582H}, doi = {10.1039/D3NR00582H}, year = {2023}, date = {2023-07-27}, journal = {Nanoscale}, pages = {-}, publisher = {The Royal Society of Chemistry}, abstract = {Controlling the vortex chirality in ferromagnetic nanodots and nanorings has been a topic of investigation for the last few years. Many control methods have been proposed and it has been found that the control is related to the breaking of the circular symmetry of the ring. In this paper, we present a theoretical study demonstrating the control of chirality in a symmetrical ferromagnetic nanoring by breaking the circular symmetry of the system by placing an elongated ferromagnetic nanoelement inside the ring. Here, the stray magnetostatic field exerted by the asymmetrically placed nanoelement determines the movement of the domain walls upon re-magnetization of the nanoring and the resulting chirality in remanence. Thus, the use of a nanoelement not only allows control of the chirality of the vortex state in an isolated ring, but also offers an opportunity to control magnetization in denser nanoring systems, as well as for spintronic and magnonic applications.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Controlling the vortex chirality in ferromagnetic nanodots and nanorings has been a topic of investigation for the last few years. Many control methods have been proposed and it has been found that the control is related to the breaking of the circular symmetry of the ring. In this paper, we present a theoretical study demonstrating the control of chirality in a symmetrical ferromagnetic nanoring by breaking the circular symmetry of the system by placing an elongated ferromagnetic nanoelement inside the ring. Here, the stray magnetostatic field exerted by the asymmetrically placed nanoelement determines the movement of the domain walls upon re-magnetization of the nanoring and the resulting chirality in remanence. Thus, the use of a nanoelement not only allows control of the chirality of the vortex state in an isolated ring, but also offers an opportunity to control magnetization in denser nanoring systems, as well as for spintronic and magnonic applications. |
4. | R Mehta, Mathieu Moalic, Maciej Krawczyk, S Saha Tunability of spin-wave spectra in a 2D triangular shaped magnonic fractals Journal of Physics: Condensed Matter, 35 (32), pp. 324002, 2023. @article{Mehta_2023, title = {Tunability of spin-wave spectra in a 2D triangular shaped magnonic fractals}, author = {R Mehta and Mathieu Moalic and Maciej Krawczyk and S Saha}, url = {https://dx.doi.org/10.1088/1361-648X/acd15f}, doi = {10.1088/1361-648X/acd15f}, year = {2023}, date = {2023-05-12}, journal = {Journal of Physics: Condensed Matter}, volume = {35}, number = {32}, pages = {324002}, publisher = {IOP Publishing}, abstract = {Reprogramming the structure of the magnonic bands during their operation is important for controlling spin waves in magnonic devices. Here, we report the tunability of the spin-wave spectra for a triangular shaped deterministic magnonic fractal, which is known as Sierpinski triangle by solving the Landau–Lifshitz–Gilbert equation using a micromagnetic simulations. The spin-wave dynamics change significantly with the variation of iteration number. A wide frequency gap is observed for a structure with an iteration number exceeding some value and a plenty of mini-frequency bandgaps at structures with high iteration number. The frequency gap could be controlled by varying the strength of the magnetic field. A sixfold symmetry in the frequency gap is observed with the variation of the azimuthal angle of the external magnetic field. The spatial distributions of the spin-wave modes allow to identify the bands surrounding the gap. The observations are important for the application of magnetic fractals as a reconfigurable aperiodic magnonic crystals.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Reprogramming the structure of the magnonic bands during their operation is important for controlling spin waves in magnonic devices. Here, we report the tunability of the spin-wave spectra for a triangular shaped deterministic magnonic fractal, which is known as Sierpinski triangle by solving the Landau–Lifshitz–Gilbert equation using a micromagnetic simulations. The spin-wave dynamics change significantly with the variation of iteration number. A wide frequency gap is observed for a structure with an iteration number exceeding some value and a plenty of mini-frequency bandgaps at structures with high iteration number. The frequency gap could be controlled by varying the strength of the magnetic field. A sixfold symmetry in the frequency gap is observed with the variation of the azimuthal angle of the external magnetic field. The spatial distributions of the spin-wave modes allow to identify the bands surrounding the gap. The observations are important for the application of magnetic fractals as a reconfigurable aperiodic magnonic crystals. |
2022 |
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3. | Mathieu Moalic, Maciej Krawczyk, Mateusz Zelent Spin-wave spectra in antidot lattice with inhomogeneous perpendicular magnetic anisotropy Journal of Applied Physics, 132 (21), pp. 213901, 2022. @article{doi:10.1063/5.0128621, title = {Spin-wave spectra in antidot lattice with inhomogeneous perpendicular magnetic anisotropy}, author = {Mathieu Moalic and Maciej Krawczyk and Mateusz Zelent}, url = {https://doi.org/10.1063/5.0128621}, doi = {10.1063/5.0128621}, year = {2022}, date = {2022-12-01}, journal = {Journal of Applied Physics}, volume = {132}, number = {21}, pages = {213901}, abstract = {Magnonic crystals are structures with periodically varied magnetic properties that are used to control collective spin-wave excitations. With micromagnetic simulations, we study spin-wave spectra in a 2D antidot lattice based on a multilayered thin film with perpendicular magnetic anisotropy (PMA). We show that the modification of the PMA near the antidot edges introduces interesting changes to the spin-wave spectra, even in a fully saturated state. In particular, the spectra split into two types of excitations: bulk modes with amplitude concentrated in a homogeneous part of the antidot lattice and edge modes with an amplitude localized in the rims of reduced PMA at the antidot edges. Their dependence on the geometrical or material parameters is distinct, but at resonance conditions fulfilled, we found strong hybridization between bulk and radial edge modes. Interestingly, the hybridization between the fundamental modes in bulk and rim is of magnetostatic origin, but the exchange interactions determine the coupling between higher-order radial rim modes and the fundamental bulk mode of the antidot lattice.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Magnonic crystals are structures with periodically varied magnetic properties that are used to control collective spin-wave excitations. With micromagnetic simulations, we study spin-wave spectra in a 2D antidot lattice based on a multilayered thin film with perpendicular magnetic anisotropy (PMA). We show that the modification of the PMA near the antidot edges introduces interesting changes to the spin-wave spectra, even in a fully saturated state. In particular, the spectra split into two types of excitations: bulk modes with amplitude concentrated in a homogeneous part of the antidot lattice and edge modes with an amplitude localized in the rims of reduced PMA at the antidot edges. Their dependence on the geometrical or material parameters is distinct, but at resonance conditions fulfilled, we found strong hybridization between bulk and radial edge modes. Interestingly, the hybridization between the fundamental modes in bulk and rim is of magnetostatic origin, but the exchange interactions determine the coupling between higher-order radial rim modes and the fundamental bulk mode of the antidot lattice. |
2. | 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. @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} } 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. |
1. | 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. @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} } 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. |