Microdynamic nature of lattice distortion and its effects on spin texture evolution behavior in skyrmion materials

Spin-lattice coupling is one of the microdynamic sources of magnetic-mechanical effect, which can significantly affect the physical properties of materials hosting the skyrmion microstructure. Recent studies found a local lattice distortion is a natural result induced by the spin-lattice coupling and the nonalignment of spin texture, and it can lead to a non-Arrhenius transport behavior of skyrmion spin texture. In this paper, we study the deep insight of the microdynamic nature of this local lattice distortion field (LLDF). Starting with a general atomistic model for the chiral magnetic system containing the intrinsic spin-lattice coupling, we propose an analytical expression of the LLDF morphology. It suggests that the LLDF is an irrational strain-field with source, and is independent of the type of skyrmion spin texture, i.e., either Bloch- or N\'eel-type. The numerical simulations results based on spin-lattice dynamics support this conjecture. Subsequently, the effects of LLDF are discussed on the transport and stability of the skyrmion spin texture, which are two key issues for the skyrmion engineering and application. From the simulation results, the LLDF is found to bring the negative effects. The presence of LLDF, (1) brings a dragging force so to reduce the moving speed of spin texture for skyrmion transport and (2) enhances the thermal fluctuation of the spin-lattice-coupled system so to reduce the skyrmion lifetime. Our study provides an underlying mechanistic understanding on the control and manipulation of the magnetic skyrmion.