Month: March 2025

A publication with Jairo Sinova on the role of magnetic dipolar interactions in skyrmion lattices has been publised in Newton.

Magnetic skyrmions are topological two-dimensional (2D) spin textures that can be stabilized at room temperature and low magnetic fields in magnetic multilayer stacks. Besides their envisioned applications in data storage and processing, these 2D quasiparticles constitute an ideal model system to study 2D particle properties. More precisely, the role of inter-particle dipolar interactions in 2D ensembles can be fully captured in skyrmion lattices. We engineer a multilayer stack hosting skyrmion lattices and increase the relevance of the dipolar coupling by increasing the number of repetitions n from to . To ascertain the impact on the spin structure, we carry out a series of imaging experiments and find a drastic change of the skyrmion size. We develop an analytical description for the skyrmion radius in the whole multilayer regime, from thin to thick film limits, identifying the key impact of the nucleation process leading to the skyrmion lattice. Our work provides a detailed understanding of the skyrmion-skyrmion interaction, clarifying the role of dipolar interactions as the multilayer stack is expanded in the z direction.

A publication with Jairo Sinova and Olena Gomonay on Curvature-Induced Magnetization of Altermagnetic Films has been publised in Physical Review Letters.

The altermagnetic nature of a large class of magnetically ordered materials is the source of a wide range of new effects. Here, we show that the merging of two areas, namely the altermagnetism and the physics of curvilinear low-dimensional magnets gives rise to a distinct novel physical effect: a curvature-induced magnetization in bend altermagnetic films. This effect opens a promising possibility for imaging of the domain structure in the magnetically compensated structures. We consider a thin film of a -wave altermagnet bent in a stretching-free manner and demonstrate that gradients of the film curvature induce a local magnetization that is approximately tangential to the film. The magnetization amplitude directly reflects the altermagnetic symmetry and depends on the direction of bending. It is maximal for the bending along directions of the maximal altermagnetic splitting of the magnon bands. A periodically bent film of sinusoidal shape possesses a total magnetic moment per period ∝2⁢4, where and are the bending amplitude and wave vector, respectively. The total magnetic moment is perpendicular to the plane of the unbent film and its direction (up or down) is determined by the bending direction. A film roll-up to a nanotube possesses a toroidal moment directed along the tube ∝/2 per one coil, where and are the coil radius and the pitch between coils. All these analytical predictions agree with numerical spin-lattice simulations.