Publications

@article{nokey,

title = {Anisotropic second-harmonic generation in superconducting nanostructures},

author = {Sara Memarzadeh and Maciej Krawczyk and Armen Gulian and Jarosław W Kłos},

url = {https://doi.org/10.1103/2kgf-28s2},

doi = {https://doi.org/10.1103/2kgf-28s2},

year  = {2026},

date = {2026-06-26},

urldate = {2026-06-26},

journal = {Physical Review B},

volume = {113},

pages = {245427 },

abstract = {Circuits based on superconducting nanostructures are among the most promising platforms for quantum computing. Understanding how device geometry governs nonlinear electrodynamics is crucial for implementing superconducting quantum technologies. However, to date, research has largely been limited to superconducting nanostructures with collinearly aligned static and dynamic applied magnetic fields. Here, we analyze the dynamics of Meissner currents and Abrikosov vortices in a superconducting nanocube exposed to combined static and microwave magnetic fields, extending the analysis to a more general excitation geometry. We demonstrate that, in a noncollinear configuration, the magnetization component parallel to the static field develops a dominant second-harmonic response under the microwave driving. This effect is strongly enhanced when Meissner currents saturate at static fields just below the thresholds for successive vortex nucleation. By numerically solving the time-dependent Ginzburg-Landau equations, we show that the response originates from Meissner-current saturation combined with the nonlinear oscillations of normal-phase indentations, yielding an anisotropic second-harmonic signal that is directionally separated from, and not overshadowed by, the first-harmonic component of the dynamic magnetization. These findings are relevant for superconducting devices that require controllable high-frequency nonlinearity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Temporal magnetic interfaces reveal damping-induced spin-wave amplification near the stripe-domain transition in ultrathin films with DMI},

author = {Krzysztof Sobucki and Paweł Gruszecki },

url = {https://doi.org/10.1038/s41524-026-02186-8},

doi = {https://doi.org/10.1038/s41524-026-02186-8},

year  = {2026},

date = {2026-06-15},

urldate = {2026-06-15},

journal = {npj Computational Materials},

abstract = {Using micromagnetic simulations and analytical theory, we study temporal magnetic interfaces in ultrathin CoFeB films with perpendicular magnetic anisotropy and interfacial Dzyaloshinskii–Moriya interaction. We show that time refraction and reflection are governed by precession ellipticity, acting as a magnonic temporal impedance, while smooth field ramps suppress temporal reflections. Near the transition from a uniform state to stripe domains, the exceptional point and critical fields delimit damping, slow-instability, and strong-instability regimes. In the slow-instability window, Gilbert damping counterintuitively drives spin-wave growth with a rate proportional to the damping parameter. Micromagnetic simulations confirm that a temporal-slab protocol exploiting this regime achieves up to 175-fold frequency-preserving amplitude amplification without continuous power injection. Energy analysis indicates that the field ramp stores energy in the metastable uniform state below the stripe-domain transition, later released into growing spin-wave excitations, consistent with the antimagnonic framework. These results establish temporal field modulation as a route to reconfigurable spin-wave gain.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Controlling the spin-wave nonreciprocity of a crescent shaped nanowire via curvature and magnetic field},

author = {Uladzislau Makartsou and Mateusz Gołębiewski and Attila Kákay and Elena Tartakovskaya and Maciej Krawczyk },

url = {https://doi.org/10.1063/5.0323993},

doi = {https://doi.org/10.1063/5.0323993},

year  = {2026},

date = {2026-06-10},

urldate = {2026-06-10},

journal = {Journal of Applied Physics},

volume = {139},

pages = {223902 },

abstract = {Recent studies on spin-wave propagation in ferromagnetic waveguides have highlighted the role of nonreciprocity resulting from the chiral nature of dipolar interactions in curved elements. However, the impact of spin-wave mode type on nonreciprocity remains unexplored. Using micromagnetic simulations supported by analytical modeling, we systematically analyzed the propagation of edge, fundamental, and width-quantized spin-wave modes in a ferromagnetic nanowire with a crescent-shaped cross section. Our results show that the strength and sign of nonreciprocity depend on the mode type, as well as on the curvature magnitude of the nanowire’s top and bottom surfaces and the strength of the external magnetic field. Interestingly, changing the mode type, for instance, induced by altering the curvature or magnetic field, results in a significant change in the dispersion relation asymmetry. This effect underscores the important role of spin-wave profiles in nonreciprocity, deepens our fundamental understanding of spin-wave dynamics in curved geometries, and paves the way for designing magnonic waveguides with tailored properties.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Capability of Dielectric Resonator Based Meta-Atoms with VO2 Components for Switchable Coding and Wavefront-Manipulating THz Metasurfaces},

author = {Andriy E Serebryannikov and Kanan Fataliyev and Atilla O. Cakmak and Evrim Colak},

url = {https://doi.org/10.3390/ma19122449},

doi = {https://doi.org/10.3390/ma19122449},

year  = {2026},

date = {2026-06-08},

urldate = {2026-06-08},

journal = {Materials },

volume = {19},

pages = {2449},

abstract = {Vanadium dioxide (VO2) is a phase-change material, which changes its properties under thermal or optical stimuli. Thanks to the fact that the material phase transition appears at conditions which are close to environmental ones, VO2 has been widely used in diverse structures, including metasurfaces, that acquire switching and reconfigurability capabilities. In this paper, we numerically study the functionality-enabling properties of dielectric resonator-based nondiffractive meta-atoms that comprise small VO2 components, i.e., covers or drops, in switchable coding and wavefront-manipulating scenarios at THz frequencies. The goal is to unveil the potential of these meta-atoms in switching the reflected wave’s phase coverage under temperature variations. The main attention is paid to how the shape and size of the VO2 components affect the functionality switching that is enabled by the changes in coverage. It is shown that metallic and insulator states of VO2 can play different roles in diverse switching scenarios. Different resonance regimes exert different influences on the resulting capability of switching, while contributing to multifunctional operating scenarios. Possible roles of state-dependent absorption are clarified.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Micrometer-range spin-wave transport by incorporating perpendicular spins in artificial spin ice},

author = {Syamlal S Kunnath and Mateusz Zelent and Paweł Gruszecki and Maciej Krawczyk},

doi = {https://doi.org/10.1103/x88f-5h48},

year  = {2026},

date = {2026-06-05},

urldate = {2026-06-05},

journal = {Physical Review B},

volume = {113},

pages = {224418 },

abstract = {Artificial spin ice (ASI) systems exhibit fascinating phenomena, such as frustration and the formation of magnetic monopole states, and Dirac strings. However, exploring the wave phenomena in these systems is elusive due to the weak dipolar coupling that governs their interactions. In this study, we demonstrate coherent spin-wave propagation in a hybrid ASI system, which is based on a multilayered ferromagnetic thin film with perpendicular magnetic anisotropy and in-plane magnetized nanoelements immersed within it. We show that this system enables spin-wave transmission over a one-micrometer distance via exchange-mediated coupling between subsystems and evanescent spin-wave tunneling through the out-of-plane magnetized parts. This system overcomes the limitations of purely dipolar interactions in standard ASIs while preserving their fundamental properties. Thus, it provides a platform for studying spin-wave phenomena in frustrated ASI systems and paves the way for exploiting them in analog signal processing with spin waves.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Angle-dependent resonant dynamics of stripes and skyrmions in Re/Co/Pt multilayers},

author = {Sukanta Kumar Jena and Kilian Lenz and Mateusz Zelent and Mathieu Moalic and Artem Lynnyk and Aleksiej Pietruczik and Paweł Aleszkiewicz and Ewelina Milińska and Jürgen Lindner and Andrzej Wawro},

doi = {https://doi.org/10.1103/78wv-b4np},

year  = {2026},

date = {2026-06-01},

urldate = {2026-06-01},

journal = {Physical Review B},

volume = {113},

pages = {214403 },

abstract = {The dynamic behavior and stabilization of skyrmions in magnetic multilayers are critical for advancing spintronic and magnonic technologies. In our study, we investigate the static and dynamic properties of [Re/Co⁡(𝑑Co)/Pt]20 multilayers with varying Co thicknesses (6–24 Å), showcasing a transition from out-of-plane to in-plane magnetic anisotropy. The magnetization reversal leads to a transformation from labyrinth domains to skyrmion bubbles due to the interfacial Dzyaloshinskii-Moriya interaction (iDMI). Using angle-dependent imaging at remanence, we confirm that skyrmions can be stabilized without an external magnetic field at specific polar angles, with the stabilization angle increasing alongside the Co thickness. Ferromagnetic resonance spectroscopy reveals four distinct resonant modes, including low-frequency (2–18 GHz) and high-frequency (20–35 GHz) modes, depending on the magnetization texture. The frequency range of these modes narrows with decreasing effective anisotropy and the iDMI strength decreases in thicker Co layers in perpendicular configurations. These findings link between material properties and skyrmion dynamics directly and demonstrate the feasibility of tunable resonant modes for magnonic devices. By addressing both static and dynamic aspects, our work advances the development of next-generation spintronic and magnonic applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Efficient generation of second-harmonic propagating spin waves in an out-of-plane-magnetized thin ferromagnetic film},

author = {Mathieu Moalic and Youenn Patat and Mateusz Zelent and Maciej Krawczyk},

doi = {https://doi.org/10.1103/xxlw-pnhs},

year  = {2026},

date = {2026-05-28},

urldate = {2026-05-28},

journal = {Physical Review Applied},

volume = {25},

pages = {054072},

abstract = {Spin waves are attractive information carriers, owing to their gigahertz-to-terahertz frequencies, nanometric wavelengths, and negligible Joule heating. However, efficiently and locally exciting short-wavelength high-frequency propagating spin waves and exploiting nonlinear effects remain challenging. We propose a hybrid ferromagnetic structure consisting of an in-plane-magnetized nanosized area (a magnonic nanocavity) that is exchange-coupled to an out-of-plane-magnetized film or stripe. Micromagnetic simulations show that a spatially uniform out-of-plane microwave magnetic field excites only the fundamental mode of the nanocavity. Its second harmonic is then coherently and efficiently launched into the extended part of the ferromagnet, yielding propagating spin waves. This process can be achieved with stripe or extended film geometries, which excite plane waves or radial spin waves, respectively. Given the simple fabrication process of degrading the anisotropy of a ferromagnetic layer with perpendicular magnetic anisotropy, the spin-wave wave front can be shaped extensively by adjusting the nanocavity geometry. Conversion efficiency can be enhanced when the frequency of the second harmonic matches a higher-order standing spin-wave frequency of the nanocavity. Furthermore, the emission frequency is tunable via the bias magnetic field or the width of the nanocavity. These findings suggest a compact route toward on-chip, short-wavelength, high-frequency nonlinear spin-wave sources for artificial neural networks.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{https://doi.org/10.1016/j.ultras.2026.108116,

title = {Multicomponent elastic softening and ferroelastic instability in RbH2AsO4: A Brillouin light scattering study},

author = {Bogusław Mróz and Z Trybuła and Sławomir Mielcarek and M Szafrański and Aleksandra Trzaskowska},

doi = {https://doi.org/10.1016/j.ultras.2026.108116},

year  = {2026},

date = {2026-04-30},

urldate = {2026-04-30},

journal = {Ultrasonics},

volume = {166},

pages = {108116},

abstract = {Brillouin light scattering was used to investigate the elastic properties of the ferroelectric crystal RbH2AsO4 (RDA) across the 

 $bar{4}2m$ → mm2 phase transition near 105  K. Sound velocities, linewidths, and intensities of eight acoustic modes were measured in the temperature range 40 – 300  K. Particular attention was given to phonons propagating in the plane perpendicular to the z–axis, where group–theoretical considerations predict anomalous elastic behavior associated with ferroelasticity. Complementary temperature-dependent X-ray diffraction measurements were performed to determine the spontaneous deformation and its evolution through the phase transition. The obtained strain behavior was compared with that of the reference hydrogen–bonded ferroelectric KH2PO4 (KDP), enabling a broader assessment of ferroelastic characteristics within this family of crystals. The results establish RDA as a model system for studying complex ferroelastic behavior involving multiple interacting elastic modes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Impact of mode hybridization on spin-wave profiles in bi-component magnonic crystals},

author = {Sławomir Mamica },

url = {https://doi.org/10.1038/s41598-026-42425-y},

doi = {10.1038/s41598-026-42425-y},

year  = {2026},

date = {2026-03-14},

urldate = {2026-03-14},

journal = {Scientific Reports},

volume = {16},

pages = {13532 },

abstract = {The study investigates mode hybridisation in two-dimensional permalloy–cobalt magnonic crystals. Calculations were performed using the plane-wave method, with particular emphasis on the effects accompanying hybridisation. A distinctive feature revealed in this work is the exchange, between hybridising modes, of the excitation concentration coefficient in the constituent materials (e.g. in cobalt). This coefficient describes the fraction of spin-wave energy concentrated within one of the components of the composite. Its analysis enables the identification of hybridisation even when other manifestations—such as profile swapping or clear branch repulsion—are only weakly pronounced. We demonstrate cases in which the exchange of the concentration coefficient occurs between hybridising modes without the typical swapping of spin-wave profiles, or with only minimal repulsion between their branches in the frequency spectrum.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Design of magnonic waveguides using surface anisotropy-induced Bragg mirrors},

author = {Grzegorz Centała and Jarosław W Kłos},

url = {https://doi.org/10.1063/5.0302506},

doi = {https://doi.org/10.1063/5.0302506},

year  = {2026},

date = {2026-02-20},

urldate = {2026-02-20},

journal = {Applied Physics Letters},

volume = {128},

pages = {073504 },

abstract = {Waveguides are fundamental components for signal transmission in integrated wave-based processing systems. In this paper, we address the challenges in designing magnonic waveguides, including limitations such as non-uniform demagnetizing fields, reduced group velocity, and restricted operating frequency ranges. We propose a magnonic waveguide design with promising properties that overcome these limitations to a significant extent. Specifically, we investigate a waveguide formed within a uniform ferromagnetic layer (⁠Co20Fe60B20⁠) by applying surface anisotropy in strip regions, thereby creating Bragg mirror structures to confine spin waves and guide them along a single direction. The proposed waveguide enables the propagation of high-frequency spin waves with high velocities in the ferromagnetic layer while minimizing static demagnetizing effects. We developed a model that allows for spin-wave confinement and guidance in two perpendicular directions by spatially modulating the surface anisotropy. The theoretical model was solved using the finite element method to calculate the dispersion relations of the waveguide modes and analyze their spatial profiles. Additionally, we determine the group velocity and localization characteristics, providing a comprehensive understanding of the waveguide's performance.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Perpendicular Magnetic Anisotropy in Thin Films Enables Extraordinary Spin-Wave Phenomena: Anti-Larmor Precession, Negative Reflection and Refraction, Multireflection and Multirefraction},

author = {Nikodem Leśniewski and Y S Dadoenkova and Florian F. L. Bentivegna and Paweł Gruszecki},

url = {https://pubs.acs.org/doi/10.1021/acsami.5c21700},

doi = {https://pubs.acs.org/doi/10.1021/acsami.5c21700},

year  = {2026},

date = {2026-02-06},

urldate = {2026-02-06},

journal = {ACS Applied Materials & Interfaces},

volume = {18},

issue = {6},

pages = {10539–10551},

abstract = {We present a theoretical and numerical investigation of the role of perpendicular magnetic anisotropy (PMA) in shaping spin-wave (SW) dynamics under low magnetic fields in thin and ultrathin magnetic films. PMA introduces an in-plane torque that counteracts exchange, dipolar, and Zeeman contributions, fundamentally modifying SW dispersion and inducing a local minimum that, under specific conditions, becomes the lowest frequency across all geometric configurations. This results in a sombrero-shaped dispersion in ultrathin films and a cowboy-hat-like shape in thicker films, where dipolar interactions dominate. Using isofrequency contour (IFC) analysis, we demonstrate that these PMA-induced dispersion shapes enable nontrivial wave phenomena unprecedented in uniform media: bireflection and negative reflection in ultrathin films and trireflection in thicker films─where a single incident beam splits into three reflected components, two with negative angles. Most remarkably, we predict and demonstrate trirefraction, where one incident beam generates three refracted beams with two exhibiting negative refraction angles. We further show anti-Larmor precession of magnetization near the dispersion minimum in thicker films, arising from the interplay between PMA-induced and dipolar torques. Systematic simulations across diverse material systems─metallic films, ferrimagnetic garnets, hybrid structures, and multilayers─confirm the universal nature of these phenomena in any PMA system supporting stripe domain transitions. These results open new opportunities to explore wave phenomena beyond magnonics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optical probing of magnons and phonons in Ni80Fe20 nanodot arrays},

author = {Arundhati Adhikaria and Piotr Graczyk and and Avinash K. Chaurasiya and Sayanti Mondala and Jarosław W Kłos and Anjan Barman},

url = {https://doi.org/10.1039/D5NR04628A},

doi = {https://doi.org/10.1039/D5NR04628A},

year  = {2026},

date = {2026-01-19},

urldate = {2026-01-19},

journal = {Nanoscale},

volume = {18},

pages = {4392-4398},

abstract = {Control of collective spin excitations by static or dynamic strain is an emerging phenomenon that requires in-depth understanding for the design of future spin-wave-regulated devices. Here, we explore mutually interacting spin waves and acoustic wave modes in addition to a few non-interactive modes through all optical excitation in ordered arrays of Ni80Fe20 nanomagnets. The acoustic wave originating from elastic deformation resonantly couples to the spin wave via the magnetoelastic effect at their overlapping frequency. We demonstrate that the choice of the lattice type in which the magnetic nanodots are arranged is crucial for the observation of the magnetoelastic interaction. Therefore, this study shows that the simultaneous existence of elastic wave and spin wave offer ingeniously advantageous features to pave the way towards energy-efficient magnetoacoustic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Mechanism of ferromagnetic resonance in ferromagnet-superconductor trilayers},

author = {Dariia Popadiuk and Julia Kharlan and Anatolii Kravets and Jarosław W Kłos and Vladimir Golub},

url = {https://doi.org/10.1103/blxk-m6pz},

doi = {https://doi.org/10.1103/blxk-m6pz},

year  = {2026},

date = {2026-01-16},

urldate = {2026-01-16},

journal = {Physical Review B},

volume = {113},

pages = {014425},

abstract = {Temperature dependent magnetic properties of superconductor-ferromagnet-superconductor (SC/FM/SC) trilayers are studied both experimentally and theoretically, with a focus on ferromagnetic resonance (FMR). The influence of the SC and FM layer thicknesses on the FMR field is examined. To differentiate the mechanisms involved, we additionally investigate structures containing nonmagnetic metallic (M) or insulating (I) spacers (SC/FM/M/SC or SC/FM/I/SC). All the studied multilayers show large reductions in the FMR field below the critical temperature of the SC, except the system containing an insulating spacer (SC/FM/I/SC). This SC-induced FMR-shift (resonance field/frequency) is larger for thicker SC as well as FM layers, reaching a saturation value for very large thicknesses. To explain the measured results, an analytical model is developed, in which the FM-magnetization precession modulates the magnetic flux in the system, thereby inducing an alternating supercurrent in the SC, which in turn produces a dynamic back-action magnetic field on the FM that shifts its resonance frequency. The model considers closed current loops, where the FM layer conductively links the supercurrents flowing in the opposite directions in the two outer SC layers. Our results provide a practical route for increasing the operating frequency of magnonic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{three_magnon,

title = {Three-magnon scattering of spin wave on edge-localized mode in thin ferromagnetic film},

author = {Julia Kharlan and R Verba and Krzysztof Sobucki and Paweł Gruszecki and Maciej Krawczyk},

url = {https://doi.org/10.1103/7rbt-2ywd},

year  = {2025},

date = {2025-12-01},

journal = {Phys. Rev. B},

abstract = {Three-wave scattering is a fascinating phenomenon with many applications in various technologies. Reducing the system symmetry greatly affects three-wave scattering, which, in this case, goes beyond the simple momentum conservation law. In this study, we examine three-magnon scattering at the edge of a thin ferromagnetic film, when a bulk spin wave interacts with an edge-localized propagating spin-wave upon the reflection. This creates new bulk spin waves at mixed frequencies by means of three-magnon confluence or stimulated splitting processes. Using our developed analytical theory, which has been confirmed by full micromagnetic simulations, we demonstrate that the amplitude of the wave generated in the stimulated splitting process is several times larger than that generated in the confluence process. This is primarily due to the lower group velocity of the wave formed in splitting process than in confluence. Furthermore, intensity of inelastically scattered waves exhibit a pronounced dependence on the incidence angle and frequency of the edge spin wave that goes beyond existing qualitative models. We show that the observed behaviors can only be explained by taking into account, that the scattered waves are created by several elementary three-magnon processes involving the incident and reflected waves. The complex nature of the scattered wave creation results in a strong sensitivity of its amplitude to the phase accumulation of spin waves upon reflection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{49pf-hw6m,

title = {Influence of photon-magnon coupling on spin-wave-excitation enhancement},

author = {Liubov Ivzhenko and S Polevoy and S Nedukh and Maciej Krawczyk},

url = {https://link.aps.org/doi/10.1103/49pf-hw6m},

doi = {10.1103/49pf-hw6m},

year  = {2025},

date = {2025-11-19},

journal = {Phys. Rev. Appl.},

volume = {24},

number = {11},

issue = {5},

pages = {054056},

abstract = {One of the main challenges in magnonics is the efficiency of the conversion of microwave signals into spin waves. This efficiency is low due to the significant mismatch between microwave and spin-wave wavelengths in the gigahertz range (10−2 and 10−8 m, respectively), leading to high energy consumption in magnonic circuits. To address this issue, we propose an approach based on a planar inverse split-ring resonator (ISRR) loaded with a thin Permalloy (Py) film and exploiting the photon-magnon coherent coupling effect. Our numerical studies show that the ISRR-based antenna achieves more than a fourfold improvement in conversion efficiency compared to a conventional single-microstrip-transmission-line antenna when working at frequencies and bias magnetic fields around the anticrossing frequency gap. This has been demonstrated in the weak photon-magnon coherent coupling regime for a nanometer-thin Py film with micrometer lateral dimensions. Further optimization of the ISRR can help to achieve the strong coherent coupling regime, making the system potentially useful for quantum technology. Our compact and efficient antenna design offers a significant advantage over standard microstrip-line antennas, paving the way for powerful magnonic circuits for microwave signal processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{mroz_1125494694,

title = {The influence of NH4 doping on the elastic properties of RbH2AsO4 crystals},

author = {Bogusław Mróz and Z Trybula and Sławomir Mielcarek and Aleksandra Trzaskowska},

doi = {10.1038/s41598-025-27078-7},

year  = {2025},

date = {2025-11-07},

urldate = {2025-11-07},

journal = {Scientific Reports},

volume = {15},

issue = {1},

pages = {39140},

abstract = {We report a systematic study of the elastic and dynamic properties of mixed Rb1-x(NH4)xH2AsO4 (RADA) crystals using high-resolution Brillouin light scattering over a broad temperature range (40–300 K). By varying the ammonium concentration, we reveal how NH4+ substitution alters the elastic stiffness tensor, phase transition temperatures, phonon damping, and order parameter relaxation dynamics. The results show a clear evolution from ferroelectric to antiferroelectric and proton-glass behavior as the ammonium content increases. We observe enhanced elastic softening, increased phonon scattering, and reduced relaxation times with doping, indicating a growing degree of structural disorder and frustration in the hydrogen-bond network. The observed changes in phonon thermal conductivity correlate with these elastic anomalies. Our findings highlight the potential of chemical substitution in tuning the mechanical and thermal properties of hydrogen-bonded ferroelectric crystals, with implications for designing adaptive low-temperature optical and memory materials.

},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{w4xn-2yff,

title = {Spin waves in the bilayer van der Waals magnet CrSBr},

author = {R den Teuling and R Das and A Bondarenko and Elena Tartakovskaya and G Bauer and Y Blanter},

doi = {10.1103/w4xn-2yff},

year  = {2025},

date = {2025-10-29},

journal = {Phys. Rev. B},

volume = {112},

number = {15},

issue = {14},

pages = {144442},

abstract = {We derive analytical expressions for the spin-wave frequencies and precession amplitudes in monolayer and antiferromagnetically coupled bilayer CrSBr under in-plane external magnetic fields. The analysis covers the antiferromagnetic, ferromagnetic, and canted phases, demonstrating that the spin-wave frequencies in all phases are tunable by the applied magnetic field. We discuss the roles of intra- and interlayer exchange interactions, triaxial anisotropy, and intralayer dynamic dipolar fields in controlling the magnetization dynamics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Rana_2025,

title = {Focus on coupling phenomena in magnonics and magnonic metamaterials},

author = {Bivas Rana and S Saha and Paweł Gruszecki and J Puebla},

doi = {10.1088/1361-648X/ae1398},

year  = {2025},

date = {2025-10-22},

urldate = {2025-10-22},

journal = {Journal of Physics: Condensed Matter},

volume = {37},

number = {43},

pages = {430201},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{zelent_acs_2025,

title = {Beyond Fixed-Size Skyrmions in Nanodots: Switchable Multistability with Ferromagnetic Rings},

author = {Mateusz Zelent and Maciej Krawczyk and K Y Guslienko},

url = {https://doi.org/10.1021/acs.nanolett.5c02678},

doi = {10.1021/acs.nanolett.5c02678},

isbn = {1530-6984},

year  = {2025},

date = {2025-09-11},

urldate = {2025-09-11},

journal = {Nano Letters},

abstract = {We demonstrate a novel approach to controlling and stabilizing magnetic skyrmions in ultrathin multilayer nanostructures through spatially engineered magnetostatic fields generated by ferromagnetic nanorings. Using analytical modeling and micromagnetic simulations, we show that the stray fields from a Co/Pd ferromagnetic ring with out-of-plane magnetic anisotropy significantly enhance the Néel-type skyrmion stability in an Ir/Co/Pt nanodot, even stabilizing the skyrmion in the absence of Dzyaloshinskii–Moriya interactions. We demonstrate precise control over the skyrmion size and stability. We observe a multistability phenomenon, where the skyrmion can be stabilized at two or more distinct equilibrium diameters depending on the ring’s magnetization orientation. These stable states exhibit energy barriers that substantially exceed thermal fluctuations at room temperature, suggesting potential applications in robust multibit memory storage. Furthermore, we demonstrate that a skyrmion can be switched between two metastable states using a suitably designed nanosecond magnetic field pulse. Our findings pave the way for advanced spintronic nanodevices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/5.0277362,

title = {Multifunctional magnonic platform based on the interplay between spin-wave waveguide and nanodots with PMA and DMI},

author = {Krzysztof Szulc and Mateusz Zelent and Maciej Krawczyk},

url = {https://doi.org/10.1063/5.0277362},

doi = {10.1063/5.0277362},

isbn = {2166-532X},

year  = {2025},

date = {2025-09-10},

journal = {APL Materials},

volume = {13},

number = {9},

pages = {091108},

abstract = {Materials with perpendicular magnetic anisotropy (PMA) and antisymmetric exchange interactions are widely explored in spintronics but are of limited use in magnonics due to high damping. We present a hybrid magnonic crystal composed of a chain of circular nanodots with strong PMA and Dzyaloshinskii–Moriya interaction (DMI), positioned above a spin-wave waveguide made of permalloy. Due to the dipolar coupling between the subsystems, a strongly bound hybrid magnetization texture is formed, with two stable magnetization states in the nanodots: a single-domain state and an egg-shaped skyrmion state, allowing reprogramming of the system properties. Numerical results show complex spin-wave spectra with several key features for magnonics: programmable Bragg and non-Bragg bandgaps correlated with magnon–magnon couplings, the flat bands and bound states for the skyrmion state, and exclusively waveguide-dominated modes for the single-domain state. With these properties, the proposed hybrid magnonic crystal has different functionalities that overcome the damping limitations of materials with PMA and DMI and open up potential applications in spin-wave filtering, spin-wave generation, quantum magnonics, and analog magnonics, in particular in the realization of magnonic neural networks.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/10.0038648,

title = {Controlling spin textures of magnetic nanodots using an antidot matrix},

author = {S A Bunyaev and G Kharchenko and R Verba and Mathieu Moalic and Maciej Krawczyk and M Urbánek and K Y Guslienko and G N Kakazei},

doi = {10.1063/10.0038648},

year  = {2025},

date = {2025-08-01},

journal = {Low Temperature Physics},

volume = {51},

number = {8},

pages = {1017-1022},

abstract = {We present a study of the magnetic properties of circular nanodots placed inside or in the vicinity of a circular hole in the perpendicularly magnetized antidot matrix. Micromagnetic simulations were performed to investigate the remanent magnetization configurations of the nanodots as a function of their vertical position relative to the matrix. The results demonstrate that the strength of the radial component of antidot matrix stray fields varies significantly along the vertical coordinate. This change influences the remanent state of nanodots, leading, depending on their location, to the stabilization of several magnetization configurations: radial vortex, curled vortex, or single-domain state. It was found that placing the dot at few nanometers below or above the matrix allows to stabilize the vortex state for a nanodot with the smallest diameter. This result provides a hint to tailor the magnetic properties of nanodots for their applications in spintronic and magnonic devices.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/10.0038642,

title = {Dipolar-exchange spin waves in thin bilayers},

author = {R den Teuling and R Das and A Bondarenko and Elena Tartakovskaya and G Bauer and Y Blanter},

url = {https://doi.org/10.1063/10.0038642},

doi = {10.1063/10.0038642},

isbn = {1063-777X},

year  = {2025},

date = {2025-08-01},

journal = {Low Temperature Physics},

volume = {51},

number = {8},

pages = {998-1003},

abstract = {We investigate the dipolar-exchange spin wave spectrum in thin ferromagnetic bilayers with in-plane magnetization, incorporating interlayer exchange coupling and intra- and interlayer dipolar interactions. In the continuum approximation, we analyze the nonreciprocity of propagating magnetic stray fields emitted by spin waves as a function of the relative orientation of the layer magnetizations that are observable by magnetometry of synthetic antiferromagnets or weakly coupled type-A van der Waals antiferromagnetic bilayers as a function of an applied magnetic field.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Achuthan2025,

title = {Influence of effective thickness in elastic anisotropy and surface acoustic wave propagation in CoFeB/Au multilayer},

author = {Amrutha V. Achutran and Sreedevi Janardhanan and P. Kuświk and Aleksandra Trzaskowska

},

url = {https://doi.org/10.1038/s41598-025-08560-8},

doi = {10.1038/s41598-025-08560-},

isbn = {2045-2322},

year  = {2025},

date = {2025-07-15},

urldate = {2025-07-15},

journal = {Scientific Reports},

volume = {15},

issue = {1},

pages = {25585},

abstract = {Surface acoustic waves (SAWs) in multilayered nanostructures represent a critical frontier in understanding material behavior at the nanoscale, with profound implications for emerging acoustic and spintronic technologies. In this study, we investigate the influence of the magnetic layer thickness on the propagation of surface acoustic waves in CoFeB-based multilayers. Two approaches to effective medium modelling are considered: treating the entire multilayer as a homogeneous medium and focusing on the region affected by light penetration. The elastic properties of the system are analyzed using Brillouin light scattering and numerical modelling, with a particular emphasis on the anisotropy of Young’s modulus and its dependence on CoFeB thickness. The results reveal a significant variation in surface acoustic wave velocity and elastic anisotropy as a function of the multilayer configuration, highlighting the role of the penetration depth in effective medium approximations. The best agreement with BLS measurements was obtained for the effective medium model limited to the optical penetration depth, highlighting the importance of light-matter interaction volume in SAW-based diagnostics. These findings provide valuable insights into the tunability of acoustic and spin-wave frequencies through structural modifications, which is crucial for developing high-performance resonators, surface acoustic wave filters, and spin-wave-based information processing devices.

},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{lehmannstructural,

title = {Structural and biomechanical analysis of femurs from mice treated with diclofenac, miR-15b and miR-365},

author = {T Lehmann and Aleksandra Trzaskowska and E Pruszyńska-Oszmałek and P Kołodziejski and M Wojtków and C Pezowicz and Sławomir Mielcarek and A Hertel and P Jagodziński and M Głowacki},

doi = {10.37190/abb/207864},

year  = {2025},

date = {2025-07-03},

journal = {Acta of Bioengineering and Biomechanics},

volume = {27},

number = {2},

abstract = {Purpose Nonsteroidal anti-inflammatory drugs (NSAIDs) are used to treat pain, but they have side effects, including the inhibition of bone healing. Diclofenac (DF), a member of the NSAID group, affects bone health adversely. One potential approach to protect bones from the effects of NSAIDs involves the administration of short nucleic acids, such as microRNAs (miRNAs). This study aimed to determine whether two specific miRNAs, miR-15b and miR-365, could mitigate the effects of DF on bone. Methods We used the C57BL/6J mouse strain and the MC3T3-E1 pre-osteoblast cell line derived from this mouse strain. Female C57BL/6J mice were treated with DF and miR-15b or miR-365 mimics. After euthanising the mice, we analysed their femurs using micro-computed tomography (μCT) and dynamic mechanical analysis (DMA). In addition, we performed experiments in cultured MC3T3-E1 cells, which were transfected with either miR-15b or miR-365. We assessed the relative mRNA levels of osteoblast differentiation markers using real-time PCR. Results Our findings indicated that miR-15b and miR-365 were effective in reversing the detrimental effects of DF on bone mineral density. DF decreased the bone’s storage modulus (E’), while miR-15b and miR-365 ameliorated this effect. In the preosteoblast MC3T3-E1 cells, DF did not significantly regulate marker genes; however, the administration of miR-15b and miR-365 reduced the gene expression of Runx2, Alp, and Satb2. Conclusions In summary, the impact of DF on the structural and mechanical properties of bone was not mediated by gene regulation in osteoblasts. However, osteoblasts were responsive to the administration of miR-15b and miR-365.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/10.0036746,

title = {Hopf index of the toroidal magnetic hopfions in cylindrical and spherical dots},

author = {K Y Guslienko and Elena Tartakovskaya},

url = {https://doi.org/10.1063/10.0036746},

doi = {10.1063/10.0036746},

isbn = {1063-777X},

year  = {2025},

date = {2025-06-01},

journal = {Low Temperature Physics},

volume = {51},

number = {6},

pages = {695-699},

abstract = {Topologically non-trivial 3D magnetization textures in the restricted curvilinear geometries are considered. 3D topological charges (the Hopf indices) are calculated for a particular case of 3D topological magnetic solitons, the toroidal hopfions in cylindrical and spherical ferromagnetic dots. The calculation method is based on the theory of toroidal hopfions developed within the classical field theory for infinite media. We exploited the property of the toroidal hopfions that the Hopf index density in any curvilinear coordinate system can be expressed as a Jacobian of the transformation from the toroidal coordinates to new coordinates, which match to the magnetic particle symmetry. The calculated Hopf indices are not integer and approach integer values increasing the dot sizes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Serebryannikov2025rman,

title = {Raman Scattering Enhancements Due to Super- and Subradiant Collective Plasmon Modes on Large-Area 2D-Au Arrays},

author = {E Mathew and Andriy E Serebryannikov and J Jenczyk and I Iatsunskyi and S Murawka and M Lewandowski and M Wiesner},

doi = {10.1021/acsami.5c04804},

year  = {2025},

date = {2025-05-22},

journal = {ACS Applied Materials & Interfaces},

abstract = {Ordered metal nanoparticle (MNP) arrays with ultrasmall interparticle gaps S exhibit strong enhancement of the electromagnetic (EM) near-field, known as hotspots, for surface-enhanced Raman spectroscopy (SERS) sensing. These arrays, with uniform gap sizes, are also essential for studying nonlinear Raman scattering effects and surface selection rules. Optical characterization of the fabricated large-area Au arrays with S ≪ r, where r is the MNP radius, revealed the excitation of hybridized-collective plasmon modes with giant EM near-field enhancement. We found that the SERS enhancement associated with a subradiant plasmon mode depends primarily on the interparticle gap distance S, rather than on the ordering of MNPs into arrays. However, arranging MNPs in the form of arrays influenced the far-field scattering of the super-radiant mode excited at a longer wavelength, resulting in lower but highly anisotropic SERS enhancements that depend on the far-field excitation polarization angle σ. This study on ordered MNP arrays with ultrasmall interparticle gaps S ≪ r highlights the roles of S and MNP ordering in SERS enhancement of an analyte. This understanding is pivotal for designing SERS substrates with very small interparticle gaps, as they generate a large number of intense and well-distributed SERS hotspots. Furthermore, an anisotropy-induced SERS dichroism effect was observed. Polarization-dependent SERS intensities varied based on the excitation wavelength λexc and its corresponding Stokes wavelength positions related to the excited plasmon mode. As a result, the SERS dichroism of lower-frequency Stokes-shifted peaks exhibited a cos2(σ) dependence, whereas higher-frequency Stokes-shifted peaks exhibited a sin2(σ) dependence. This observation validates the EM near-field mechanism of SERS. The fabricated large-area 2D-Au arrays meet most of the essential requirements for efficient, robust, and reliable large-area SERS sensing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{D4NH00618F,

title = {Nucleation and arrangement of Abrikosov vortices in hybrid superconductor–ferromagnet nanostructures},

author = {Sara Memarzadeh and Mateusz Gołębiewski and Maciej Krawczyk and Jarosław W Kłos},

doi = {10.1039/D4NH00618F},

year  = {2025},

date = {2025-05-21},

urldate = {2025-05-21},

journal = {Nanoscale Horiz.},

abstract = {This study investigates the nucleation{,} dynamics{,} and stationary configurations of Abrikosov vortices in hybrid superconductor–ferromagnet nanostructures subjected to inhomogeneous magnetic fields generated by a ferromagnetic nanodot. Employing the simulations based on time-dependent Ginzburg–Landau coupled with Maxwell{'}s equations{,} we reveal the evolution of curved vortex structures that exhibit creep-like deformation before stabilizing. The interplay between vortices and currents confined within the superconducting nanoelement gives rise to unconventional stationary vortex arrangements{,} which evolve gradually with increasing magnetic field strength—a behavior absent in homogeneous fields. Our numerical results illustrate how the ferromagnetic element can control vortex configurations via a stray magnetic field—insights that are difficult to access experimentally or analytically. We demonstrate that the superconducting nanoelement can stabilize into distinct vortex states in response to even small system perturbations. This highlights the extreme sensitivity of the system and the richness of its dynamic behaviour{,} revealing complex pinning mechanisms and providing valuable insights into the optimisation of nanoscale superconducting systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{popadiuk2024spin,

title = {Spin waves in Co2FeGe films},

author = {Dariia Popadiuk and A Vovk and S A Bunyaev and G N Kakazei and J P Araujo and P Strichovanec and P A Algarabel and V Golub and A Kravets and V Korenivski and Aleksandra Trzaskowska},

url = {https://doi.org/10.1063/5.0255241},

year  = {2025},

date = {2025-03-25},

urldate = {2025-03-25},

journal = {J. Appl. Phys. },

volume = {137},

pages = {123902 },

abstract = {The dynamic magnetic properties of full Heusler alloy thin films of Co2FeGe, grown on MgO (001) substrates under different thermal conditions, were investigated. Brillouin light scattering and ferromagnetic resonance measurements revealed that depositing at room temperature followed by annealing at 300  C for 1 h produces the best results for maximizing magnetization, exchange stiffness, and minimizing spin-dynamic dissipation in the films, which are desirable characteristics for high-speed spintronic devices. Additionally, strong hybridization of spin waves in the Damon–Eshbach geometry was observed, which is attractive for applications in magnonic signal processing circuits.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{serebryannikov2025effects,

title = {Effects of gradual deformation of identical and nonidentical, rotated and nonrotated U-shaped subwavelength resonators in few-layer metasurfaces},

author = {Andriy E Serebryannikov and A O Cakmak and E Colak},

url = {https://doi.org/10.1038/s41598-025-88678-x},

year  = {2025},

date = {2025-03-06},

journal = {Scientific Reports},

volume = {15},

number = {1},

pages = {7873},

abstract = {Raising of negative-index medium has been going hand-by-hand with the exploration of quasiplanar subwavelength resonators. Now they are widely used in modern microwave, terahertz, and infrared devices, as well as in advanced physics research. Effects of stacking of the arrays of subwavelength resonators in one few-layer metasurface is connected with the key problems of modern electrical engineering, applied physics, and beyond. Recently, the interest to subwavelength resonators has been growing due to the progress in topological photonics and non-Hermitian photonics. In this paper, the selected effects of arrays coupling in a few-layer metasurface are revisited with yet uncommon focus, i.e., survival and (dis)appearance of subwavelength resonances at the gradual deformation of the resonators at a given lattice period. Microwave frequency range has been chosen to illustrate the concept. The case when the metasurfaces comprise two periodically placed U-shaped resonator arrays is considered. The sizes of the resonators are either varied simultaneously for both front-side and back-side arrays or for the back-side array only. The main purpose of this study is to explore the basic scenarios of resonance evolution in the space of geometrical parameters. It is shown that different resonances may be sensitive to the variations in geometrical parameters and to the dissimilarity between the front-side and back-side arrays to a different extent. The obtained results point to the existence of the bands, resonances, polarization-conversion and related asymmetric transmission regimes that are robust to the deformations. They can serve as the starting point in understanding the functional capability of the physical features while adjusting the size for a much wider variety of the types of subwavelength resonators. Their unveiling promises a wide avenue towards the realization of new frequency-domain and angle-domain filters, ultrathin polarization-plane convertors, asymmetric transmission devices and advanced microwave antennas.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{sankaran2024enhancement,

title = {Enhancement of Dynamical Coupling in Artificial Spin-Ice Systems by Incorporating Perpendicularly Magnetized Ferromagnetic Matrix},

author = {Syamlal S Kunnath and Mateusz Zelent and Mathieu Moalic and Maciej Krawczyk},

doi = {https://doi.org/10.1002/sstr.202400627},

year  = {2025},

date = {2025-02-25},

urldate = {2025-02-25},

journal = {Small Structures},

pages = {2400627},

abstract = {Artificial spin-ice (ASI) systems, consisting of arrays of interacting ferromagnetic nanoelements, offer a versatile platform for reconfigurable magnonics with potential in GHz logic and neuromorphic computing. However, weak dipolar coupling between nanoelements severely limits their functionality. A rich spin-wave spectrum is numerically demonstrated in an ASI structure immersed in a perpendicularly magnetized ferromagnetic matrix, which is different from a conventional ASI system. A strong magnon–magnon coupling is observed between the bulk second-order mode of the ASI and the fundamental mode of the matrix, supported by a pronounced anticrossing frequency gap. It is shown that, in addition to the internanoelement dipolar coupling, exchange interactions at the nanoelement-matrix interface play a crucial role in this hybridization. Furthermore, the strength of the coupling can be enhanced by almost 40% just by reconfiguring the magnetization at the vertices from low-energy to high-energy monopole states. These results open the way to exploit ASI systems for magnonic applications, taking advantage of the strong coupling and vertex-dependent dynamics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{gubbiotti20252025,

title = {2025 roadmap on 3D nanomagnetism},

author = {G Gubbiotti and Maciej Krawczyk and al.},

doi = {10.1088/1361-648X/ad9655},

year  = {2025},

date = {2025-02-19},

urldate = {2025-02-19},

journal = {Journal of Physics: Condensed Matter},

volume = {37 },

pages = {143502},

abstract = {The transition from planar to three-dimensional (3D) magnetic nanostructures represents a significant advancement in both fundamental research and practical applications, offering vast potential for next-generation technologies like ultrahigh-density storage, memory, logic, and neuromorphic computing. Despite being a relatively new field, the emergence of 3D nanomagnetism presents numerous opportunities for innovation, prompting the creation of a comprehensive roadmap by leading international researchers. This roadmap aims to facilitate collaboration and interdisciplinary dialogue to address challenges in materials science, physics, engineering, and computing. The roadmap comprises eighteen sections, roughly divided into three blocks. The first block explores the fundamentals of 3D nanomagnetism, focusing on recent trends in fabrication techniques and imaging methods crucial for understanding complex spin textures, curved surfaces, and small-scale interactions. Techniques such as two-photon lithography and focused electron beam-induced deposition enable the creation of intricate 3D architectures, while advanced imaging methods like electron holography and synchrotron x-ray tomography provide nanoscale spatial resolution for studying magnetization dynamics in three dimensions. Various 3D magnetic systems, including coupled multilayer systems, artificial spin-ice, magneto-plasmonic systems, topological spin textures, and molecular magnets are discussed. The second block introduces analytical and numerical methods for investigating 3D nanomagnetic structures and curvilinear systems, highlighting geometrically curved architectures, interconnected nanowire systems, and other complex geometries. Finite element methods are emphasized for capturing complex geometries, along with direct frequency domain solutions for addressing magnonic problems. The final block focuses on 3D magnonic crystals and networks, exploring their fundamental properties and potential applications in magnonic circuits, memory, and spintronics. Computational approaches using 3D nanomagnetic systems and complex topological textures in 3D spintronics are highlighted for their potential to enable faster and more energy-efficient computing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Sobucki2025,

title = {Goos–Hänchen shift of inelastically scattered spin-wave beams and cascade nonlinear magnon processes},

author = {Krzysztof Sobucki and I L Lyubchanskii and Maciej Krawczyk and Paweł Gruszecki},

url = {https://doi.org/10.1038/s41598-025-86879-y},

doi = {10.1038/s41598-025-86879-y},

issn = {2045-2322},

year  = {2025},

date = {2025-02-14},

journal = {Scientific Reports},

volume = {15},

number = {5538},

issue = {1},

abstract = {We study, using micromagnetic simulations, the inelastic scattering of spin-wave beams on edge-localized spin-wave modes in a thin ferromagnetic film. In the splitting and confluence processes, the new spin-wave beams are generated with frequencies shifted by the edge-mode frequency. We report that inelastically scattered spin-wave beams in both processes not only change their direction of propagation but also undergo lateral shifts along the interface, analogous to the Goos–Hänchen effect known in optics. These shifts of inelastically scattered beams, for a few special cases described in the paper, can be in the range of several wavelengths, which is larger than the Goos–Hänchen shift of elastically reflected beam. Unexpectedly, at selected frequencies, we found a significant increase in the value of the lateral shifts of the scattered spin-wave beams formed in the confluence process. We show that this effect is associated with the cascading nonlinear processes taking place at the edge of the film and involving the primary edge spin wave. Our results make an important contribution to the understanding of the nonlinear nature of spin waves and provide a way to exploit it in signal processing with magnons.

},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GOLEBIEWSKI2025120499,

title = {Magnetic field controlled surface localization of ferromagnetic resonance modes in 3D nanostructures},

author = {Mateusz Gołębiewski and Krzysztof Szulc and Maciej Krawczyk},

url = {https://www.sciencedirect.com/science/article/pii/S1359645424008486},

doi = {https://doi.org/10.1016/j.actamat.2024.120499},

year  = {2025},

date = {2025-01-15},

urldate = {2024-11-05},

journal = {Acta Materialia},

volume = {283},

pages = {120499},

abstract = {By extending the current understanding and use of magnonics beyond conventional planar systems, we demonstrate the surface localization of ferromagnetic resonance (FMR) modes through the design of complex three-dimensional nanostructures. Using micromagnetic simulations, we systematically investigate woodpile-like scaffolds and gyroids — periodic chiral entities characterized by their triple junctions. The study highlights the critical role of demagnetizing fields and exchange energy in determining the FMR responses of 3D nanosystems, especially the strongly asymmetric distribution of the spin-wave mode over the system’s height. Importantly, the top–bottom dynamic switching of the surface mode localization across the structures in response to changes in magnetic field orientation provides a new method for controlling magnetization dynamics. The results demonstrate the critical role of the geometric features in dictating the dynamic magnetic behavior of three-dimensional nanostructures, paving the way for both experimental exploration and practical advances in 3D magnonics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Baranowski2025,

title = {High resolution Brillouin spectroscopy of the surface acoustic waves in Sb2Te3 van der Waals single crystals},

author = {J Baranowski and Bogusław Mróz and Sławomir Mielcarek and I Iatsunskyi and Aleksandra Trzaskowska},

url = {https://doi.org/10.1038/s41598-025-85742-4},

doi = {10.1038/s41598-025-85742-4},

issn = {2045-2322},

year  = {2025},

date = {2025-01-08},

urldate = {2025-01-08},

journal = {Scientific Reports},

volume = {15},

number = {1358},

issue = {1},

abstract = {High-resolution Brillouin spectroscopy was employed to investigate the anisotropy in surface wave velocities within a bulk single crystal of Sb2Te3, a well-known layered van der Waals material. By leveraging the bulk elastic constants derived from various simulation methods, we were able to theoretically calculate the distribution of surface acoustic phonon velocities on the cleavage plane of the material. Upon analyzing multiple simulation results, it became evident that the most significant discrepancies arose in the calculations of the elastic constant c33, with values ranging from 48 to 98 GPa. Consequently, a direct measurement of the c33 elastic constant for Sb2Te3 was attempted. Through our ellipsometry results, we determined both the real and imaginary components of the refractive index, leading to an experimental determination of the c33 elastic constant, which was found to be 47.9 GPa. Additionally the results of the conducted studies enabled the analytical determination of all components of the elastic property tensor of the investigated material.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevB.110.184410,

title = {Spin wave frequency hysteresis in Ir/Co/Pt multilayers with Dzyaloshinskii-Moriya interaction},

author = {R Gieniusz and Paweł Gruszecki and J Kisielewski and A K Dhiman and M Matczak and Z Kurant and I Sveklo and U Guzowska and M Tekielak and Maciej Krawczyk and F Stobiecki and A 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},

number = {11},

issue = {18},

pages = {184410},

abstract = {The results of extensive combined experimental and theoretical investigations of static and dynamic properties of an Ir/Co/Pt multilayer with low uniaxial anisotropy and asymmetric Ir/Co and Co/Pt interfaces responsible for large interfacial Dzyaloshinskii-Moriya interaction (IDMI) are presented. Within longitudinal magneto-optical Kerr effect-based microscopy and magnetic force microscopy studies a complex magnetic configuration was detected: Large in-plane magnetized domains several dozen micrometers in size were modulated by a weak stripe domain pattern with periods of about 100 nm. Using Brillouin light scattering spectrometry, the hysteresis of the Stokes and anti-Stokes peaks frequencies was observed as a function of the magnetic field. This hysteretic behavior associated with IDMI-induced asymmetry of spin wave dispersion is correlated with the switching of the large macrodomains. Using micromagnetic simulations, we determine field-dependent magnetization distributions and dispersion relations, proposing an explanation of the observed behavior. The investigated nanostructure can be used as a nonvolatile spin wave velocity switcher.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{sym16111482,

title = {Phason and Amplitudon Modes in K3Na(SeO4)2 Crystal},

author = {M Kaczmarski and J Jenczyk and Bogusław Mróz},

url = {https://www.mdpi.com/2073-8994/16/11/1482},

doi = {10.3390/sym16111482},

year  = {2024},

date = {2024-11-06},

journal = {Symmetry},

volume = {16},

number = {11},

abstract = {For the first time, the Nambu–Goldstone optical mode has been observed in ferroelastic crystals. The amplitudon and phason modes were identified in the Raman spectra of the K3Na(SeO4)2 (KNSe) crystal. We discuss the occurrence of such lattice vibration with regard to the possible presence of an incommensurate (IC) phase. The potential scenario of the dynamics of the SO4 tetrahedron leading to the appearance of an IC phase, accompanied by critical temperature behavior of two external vibrations of Ag symmetry, is given together with the molecular mechanism of the phase transitions in the material studied. The effect of the spatial reorganization of the crystal lattice associated with the ferroelastic domains of the KNSe crystal of W and W′ types is also discussed. We show that the emergence of such a domain structure may also be a source of incommensurability.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/5.0227380,

title = {Reconfigurable magnonic crystals: Spin wave propagation in Pt/Co multilayer in saturated and stripe domain phase},

author = {A K Dhiman and Nikodem Leśniewski and R Gieniusz and J Kisielewski and P Mazalski and Z Kurant and M Matczak and F Stobiecki and Maciej Krawczyk and A Lynnyk and A Maziewski and Paweł Gruszecki},

url = {https://doi.org/10.1063/5.0227380},

doi = {10.1063/5.0227380},

year  = {2024},

date = {2024-11-04},

urldate = {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}

}

@article{Kharlan2024,

title = {Tunable magnonic crystal in a hybrid superconductor–ferrimagnet nanostructure},

author = {Julia Kharlan and Krzysztof Szulc and Jarosław W Kłos and Grzegorz Centała},

url = {https://doi.org/10.1038/s41598-024-75492-0},

doi = {10.1038/s41598-024-75492-0},

year  = {2024},

date = {2024-10-26},

journal = {Scientific Reports},

volume = {14},

issue = {1},

pages = {25594},

abstract = {One of the most intriguing properties of magnonic systems is their reconfigurability, where an external magnetic field alters the static magnetic configuration to influence magnetization dynamics. In this paper, we present an alternative approach to tunable magnonic systems. We studied theoretically and numerically a magnonic crystal induced within a uniform magnetic layer by a periodic magnetic field pattern created by the sequence of superconducting strips. We showed that the spin-wave spectrum can be tuned by the inhomogeneous stray field of the superconductor in response to a small uniform external magnetic field. Additionally, we demonstrated that modifying the width of superconducting strips and separation between them leads to the changes in the internal field which are unprecedented in conventional magnonic structures. The paper presents the results of semi-analytical calculations for realistic structures, which are verified by finite-element method computations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/5.0233693,

title = {Role of voltage-controlled magnetic anisotropy in the recent development of magnonics and spintronics},

author = {Bivas Rana

},

url = {https://doi.org/10.1063/5.0233693},

doi = {10.1063/5.0233693},

year  = {2024},

date = {2024-10-16},

journal = {Journal of Applied Physics},

volume = {136},

number = {15},

pages = {150701},

abstract = {With significant recent progress in the thin film deposition and nanofabrication technology, a number of physical phenomena occur at the interfaces of magnetic thin films, and their heterostructures have been discovered. Consequently, the electric field-induced modulation of those interfacial properties mediated through spin–orbit coupling promises to develop magnetic material based smarter, faster, miniaturized, energy efficient spintronic devices. Among them, the electric field-induced modification of interfacial magnetic anisotropy, popularly termed as voltage-controlled magnetic anisotropy (VCMA), has attracted special attention because of its salient features. This article is devoted to reviewing the recent development of magnonics, which deals with collective precessional motion of ordered magnetic spins, i.e., spin waves (SWs), and skyrmions with chiral spin textures, with VCMA, including the perspectives of this research field. Starting with a broad introduction, the key features of VCMA and its advantages over other electric field-induced methods are highlighted. These are followed by describing the state-of-the-art of VCMA, and various other direct and indirect electric field-induced methods for magnetization reversal; controlling skyrmion dynamics; excitation, manipulation, and channeling of SWs; and tailoring magnonic bands. The critical challenges, their possible solutions, and future perspectives of this field are thoroughly discussed throughout the article.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GRACZYK2025116120,

title = {Generation of femtosecond spin-polarized current pulses at Fe/MgO interface by quasi-static voltage},

author = {Piotr Graczyk and M Pugaczowa-Michalska and Maciej Krawczyk},

url = {https://www.sciencedirect.com/science/article/pii/S1386947724002248},

doi = {https://doi.org/10.1016/j.physe.2024.116120},

issn = {1386-9477},

year  = {2024},

date = {2024-10-04},

journal = {Physica E: Low-dimensional Systems and Nanostructures},

volume = {165},

pages = {116120},

abstract = {The generation of short spin-current pulses is essential for fast spintronic devices. So far, spin current pulses are generated by femtosecond laser pulses which drive spins from a ferromagnetic metal layer. However, the need for miniaturization, simplicity and energy efficiency favour electric-field control of spintronic devices over optic or thermal control. Here, we combine ab initio calculations of electronic density of states at MgO/Fe interface with continuous model for charge transport to investigate the dynamics of the spin-dependent potential. We demonstrate that the voltage-driven instability of the electronic band structure due to the electronic resonant states at the Fe/MgO interface results in the generation of the femtosecond spin-polarized current pulse with the spin polarization up to P=7 00 % that propagates from the interface to the bulk. The dynamics of the current pulses driven by the Stoner instability depends neither on the dielectric relaxation time nor on the details of how the instability is achieved by changing the voltage, i.e. as long as the voltage changes are slow (quasi-static) with respect to the time determined by the spin diffusion constant, being of the order of fs. The presence of the instability can be detected by THz time-domain spectroscopy or pump-probe techniques.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mamica2024Spinwavemodecoupling,

title = {Spin-wave mode coupling in the presence of the demagnetizing field in cobalt-permalloy magnonic crystals},

author = {Sławomir Mamica},

url = {https://doi.org/10.1038/s41598-024-74923-2},

doi = {10.1038/s41598-024-74923-2},

year  = {2024},

date = {2024-10-03},

journal = {Scientific Reports},

volume = {14},

issue = {1},

pages = {22966},

abstract = {We present the results of studies on the non-uniform frequency shift of spin wave spectrum in a two-dimensional magnonic crystal of cobalt/permalloy under the influence of external magnetic field changes. We investigate the phenomenon of coupling of modes and, as a consequence, their hybridization. By taking advantage of the fact that compressing the crystal structure along the direction of the external magnetic field leads to an enhancement of the demagnetizing field, we analyse its effect on the frequency shift of individual modes depending on their concentration in Co. We show that the consequence of this enhancement is a shift in the coupling of modes towards higher magnetic fields. This provides a potential opportunity to design which pairs of modes and in what range of fields hybridization will occur.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Shekhar2024Effect,

title = {Effect of the underlayer on the elastic parameters of the CoFeB/MgO heterostructures},

author = {Shashank Shekhar and Sławomir Mielcarek and Y Otani and Bivas Rana and Aleksandra Trzaskowska},

url = {https://doi.org/10.1038/s41598-024-71110-1},

doi = {10.1038/s41598-024-71110-1},

year  = {2024},

date = {2024-08-31},

urldate = {2024-08-31},

journal = {Scientific Reports},

volume = {14},

issue = {1},

pages = {20259},

abstract = {We investigated the thermally induced surface acoustic waves in CoFeB/MgO heterostructures with different underlayer materials. Our results show a direct correlation between the density and elastic parameters of the underlayer materials and the surface phonon dispersion. Using finite element method-based simulations, we calculate the effective elastic parameters (such as elastic tensor, Young’s modulus, and Poisson’s ratio) for multilayers with different underlayer materials. The simulation results, either considering the elastic parameters of individual layers or considering the effective elastic parameters of whole stacks, exhibit good agreement with the experimental data. This study will help us deepen our understanding of phonon properties and their interactions with other quasiparticles or magnetic textures with the help of these estimated elastic properties.

},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mehta2024,

title = {Magnetization dynamics in quasiperiodic magnonic crystals},

author = {R Mehta and Bivas Rana and S Saha},

doi = {10.1088/1361-648X/ad5ee8},

year  = {2024},

date = {2024-08-08},

journal = {Journal of Physics: Condensed Matter},

volume = {36 },

number = {44},

pages = {443003},

abstract = {Quasiperiodic magnonic crystals, in contrast to their periodic counterparts, lack strict periodicity which gives rise to complex and localised spin wave spectra characterized by numerous band gaps and fractal features. Despite their intrinsic structural complexity, quasiperiodic nature of these magnonic crystals enables better tunability of spin wave spectra over their periodic counterparts and therefore holds promise for the applications in reprogrammable magnonic devices. In this article, we provide an overview of magnetization reversal and precessional magnetization dynamics studied so far in various quasiperiodic magnonic crystals, illustrating how their quasiperiodic nature gives rise to tailored band structure, enabling unparalleled control over spin waves. The review is concluded by highlighting the possible potential applications of these quasiperiodic magnonic crystals, exploring potential avenues for future exploration followed by a brief summary.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ivzhenko_2024,

title = {Existence of edge modes in periodic microstrip transmission line},

author = {A Girich and Liubov Ivzhenko and G Kharchenko and S Polevoy and S Tarapov and Maciej Krawczyk and Jarosław W Kłos},

url = {https://doi.org/10.1038/s41598-024-67610-9



},

year  = {2024},

date = {2024-07-16},

urldate = {2024-07-16},

journal = {Scientific Reports},

volume = {14},

number = {16477},

abstract = {The microstrip of modulated width is a realization of a one-dimensional photonic crystal operating in the microwave regime. Like any photonic crystal, the periodic microstrip is characterised by the presence of frequency bands and band gaps that enable and prohibit wave propagation, respectively. The frequency bands for microstrip of the symmetric unit cell can be distinguished by 0 or pi Zak phase. The sum of these topological parameters for all bands below a given frequency gap determines the value of the surface impedance at the end of the microstrip. We demonstrate that edge modes are absent in a finite microstrip terminated at both ends in the centres of unit cells, but they can be induced by adding the defected cells. Edge modes present at both ends of the microstrip enable microwave tunneling with high transitivity in the frequency gap with or without a change in phase. This has been demonstrated experimentally and developed in detail using numerical simulations and model calculations. The investigated system, with a doublet of edge modes in the frequency gap, can be considered as a narrow passband filter of high selectivity and characterised by a significant group delay.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{zdunek_multilayers,

title = {Investigation of phonons and magnons in [Ni80Fe20/Au/Co/Au]N multilayers},

author = {Miłosz Zdunek and Shashank Shekhar and Sławomir Mielcarek and Aleksandra Trzaskowska},

doi = {10.1088/1361-648X/ad5486},

year  = {2024},

date = {2024-06-18},

journal = {Journal of Physics: Condensed Matter},

volume = {36},

number = {37},

pages = {375801},

abstract = {The interaction between phonons and magnons is a rapidly developing area of research, particularly in the field of acoustic spintronics. To discuss this interaction, it is necessary to observe two different waves (acoustic and spin waves) with the same frequency and wavelength. In the Ni80Fe20/Au/Co/Au system deposited on a silicon substrate, we observe the interaction between spin waves and surface acoustic waves using Brillouin light scattering spectroscopy. As a result, we can selectively control (activate or deactivate) the magnetoelastic interaction between the fundamental spin wave mode and surface acoustic waves. This is achieved by adjusting the magnetostrictive layer thickness in the multilayer. We demonstrate that by adjusting the number of layers in a multilayer structure, it is possible to precisely control the dispersion of surface acoustic waves while having minimal impact on the fundamental spin wave mode.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Flebus_2024,

title = {The 2024 magnonics roadmap},

author = {B Flebus and D Grundler and Bivas Rana and Y Otani and I Barsukov and A Barman and G Gubbiotti and P Landeros and J Akerman and U Ebels and P Pirro and V E Demidov and K Schultheiss and G Csaba and Q Wang and F Ciubotaru and D E Nikonov and P Che and R Hertel and T Ono and D Afanasiev and J Mentink and T Rasing and B Hillebrands and S V Kusminskiy and W Zhang and C R Du and A Finco and T van der Sar and Y K Luo and Y Shiota and J Sklenar and T Yu and J Rao},

url = {https://dx.doi.org/10.1088/1361-648X/ad399c},

doi = {10.1088/1361-648X/ad399c},

year  = {2024},

date = {2024-06-14},

urldate = {2024-06-14},

journal = {Journal of Physics: Condensed Matter},

volume = {36},

number = {36},

pages = {363501},

abstract = {Magnonics is a research field that has gained an increasing interest in both the fundamental and applied sciences in recent years. This field aims to explore and functionalize collective spin excitations in magnetically ordered materials for modern information technologies, sensing applications and advanced computational schemes. Spin waves, also known as magnons, carry spin angular momenta that allow for the transmission, storage and processing of information without moving charges. In integrated circuits, magnons enable on-chip data processing at ultrahigh frequencies without the Joule heating, which currently limits clock frequencies in conventional data processors to a few GHz. Recent developments in the field indicate that functional magnonic building blocks for in-memory computation, neural networks and Ising machines are within reach. At the same time, the miniaturization of magnonic circuits advances continuously as the synergy of materials science, electrical engineering and nanotechnology allows for novel on-chip excitation and detection schemes. Such circuits can already enable magnon wavelengths of 50 nm at microwave frequencies in a 5G frequency band. Research into non-charge-based technologies is urgently needed in view of the rapid growth of machine learning and artificial intelligence applications, which consume substantial energy when implemented on conventional data processing units. In its first part, the 2024 Magnonics Roadmap provides an update on the recent developments and achievements in the field of nano-magnonics while defining its future avenues and challenges. In its second part, the Roadmap addresses the rapidly growing research endeavors on hybrid structures and magnonics-enabled quantum engineering. We anticipate that these directions will continue to attract researchers to the field and, in addition to showcasing intriguing science, will enable unprecedented functionalities that enhance the efficiency of alternative information technologies and computational schemes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Serebryannikov_Few_layer_bifunctional,

title = {Few-layer bifunctional metasurfaces enabling asymmetric and symmetric polarization-plane rotation at the subwavelength scale},

author = {M Gokkavas and T F Gundogdu and E Ozbay and Andriy E Serebryannikov},

url = {https://doi.org/10.1038/s41598-024-62073-4

},

doi = {10.1038/s41598-024-62073-4},

year  = {2024},

date = {2024-06-13},

journal = {Scientific Reports},

volume = {14},

issue = {1},

pages = {13636},

abstract = {We introduce and numerically validate the concept of few-layer bifunctional metasurfaces comprising two arrays of quasiplanar subwavelength resonators and a middle grid (array of rectangular holes) that offer both symmetric and asymmetric transmissions connected, respectively, with symmetric and asymmetric polarization-plane rotation functionalities. The proposed structures are thinner than $$lambda /7$$and free of diffractions. Usually, the structure’s symmetry or asymmetry, i.e. unbroken or broken spatial inversion symmetries, are considered for metasurfaces as prerequisites of the capability of symmetric or asymmetric conversion of linearly polarized waves, respectively. Due to the achieved adjustment of the resonances enabling the rotation of the polarization plane simultaneously for both orthogonal polarizations of the incident wave, the symmetric polarization-plane rotation functionality can be obtained within one subwavelength band, whereas the asymmetric polarization-plane rotation functionality associated with the asymmetric transmission is obtained within another subwavelength band. This combination of the functionalities in one subdiffraction structure is possible due to the optimal choice of the grid parameters, since they may strongly affect the coupling between the two resonator arrays. Although normal incidence is required for the targeted bifunctionality, the variations of the incidence angle can also be exploited for the enrichment of the overall functional capability. Variations of the polarization angle give another important degree of freedom. The connection between the polarization-angle dependence of cross-polarized transmission and capability of symmetric and asymmetric polarization-plane rotation functionalities is highlighted. The feasible designs of the bifunctional metasurfaces are discussed.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{PhysRevApplied.21.064007,

title = {Spin-wave confinement in a hybrid superconductor-ferrimagnet nanostructure},

author = {Julia Kharlan and Krzysztof Sobucki and Krzysztof Szulc and Sara Memarzadeh and Jarosław W Kłos},

url = {https://doi.org/10.1103/PhysRevApplied.21.064007},

doi = {10.1103/PhysRevApplied.21.064007},

year  = {2024},

date = {2024-06-05},

urldate = {2024-06-05},

journal = {Phys. Rev. Appl.},

volume = {21},

number = {16},

issue = {6},

pages = {064007},

abstract = {Eddy currents in a superconductor shield the magnetic field in its interior and are responsible for the formation of a magnetic stray field outside of the superconducting structure. The stray field can be controlled by the external magnetic field and affect the magnetization dynamics in the magnetic system placed in its range. In the case of a hybrid system consisting of a superconducting strip placed over a magnetic layer, we theoretically predict the confinement of spin waves in the well of the static stray field. The number of bound states and their frequencies can be controlled by an external magnetic field. We present the results of semianalytical calculations complemented by numerical modeling.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}