Strain-Driven Skyrmion Dynamics via Spin-Lattice Dynamics

Skyrmions are topologically protected spin textures with promising applications in spintronics due to their nanoscale size, mobility, and stability. Accurately modeling their behavior under external perturbations, such as mechanical strain, requires approaches that go beyond conventional micromagnetic or spin dynamics simulations. In this work, we use Spin-Lattice Dynamics (SLD) simulations implemented in LAMMPS to investigate the influence of uniaxial strain on skyrmion properties in two-dimensional magnetic systems. Unlike micromagnetic or standard spin dynamics approaches, SLD allows for the fully atomistic treatment of coupled spin and lattice degrees of freedom, enabling us to capture strain-induced effects with higher fidelity, including local lattice distortions and thermal fluctuations.

Our model incorporates Heisenberg exchange, Zeeman coupling under an external magnetic field and Dzyaloshinskii-Moriya interactions (DMI) both in-plane and out-of-plane. To enable the study of both DMI components, we performed a modification of the LAMMPS SPIN package code to slightly modify its implementation. We present preliminary results showing that mechanical strain can significantly affect skyrmion size, density, velocity, diffusivity, and stability, and can induce phase transitions between gas, liquid, crystal, and skyrmion-antiskyrmion states. These effects are interpreted in terms of the strain-induced modulation of exchange and DMI interactions.