Switching of skyrmion states by uniaxial deformations and stability of skyrmions in elastic ferromagnetic film

Magnetic skyrmions represent a certain type of topologically protected quasiparticles, which are necessarily stable in relation to a wide range of external magnetic fields temperatures. Skyrmions retain their vortical magnetic structure in a physical space both in the ground state and at room temperatures thanks to the combination of competing exchange interaction, Dzyaloshinskii-Moriya interaction and external magnetic field, which may arise on the surface of magnetic layers. From the energy effectiveness point of view, the process of switching skyrmion states in magnetic multilayer structures is significantly more perspective for real world applications such as piezomagnetic switches, ultra-dense magnetic memory units, detectors of weak fields and other spintronic devices, compared to the classic domain reorientation process, despite the dependence of magnetic properties of such materials on film thickness. In this article a single-layer ferromagnetic film with triangular symmetry was simulated, in which the exchange interaction and the Dzyaloshinskii-Moriya interaction depend on the distance between neighboring spins, and lattice sites are represented as mobile point bodies with unit mass, connected to neighbor sites by elastic force. Film stretching was modeled by displacing the edge sites and calculating the equilibrium positions of the remaining sites, and the ground state was calculated using the steepest descent method. The processes of switching individual skyrmion states using a combination of external magnetic fields of various intensities and various uniaxial stretching as well as stability of the skyrmion lattice were studied.