Influence of Dzyaloshinskii-Moriya Interaction on Spin Waves and Magnon Spin Transport

Abstract

Dzyaloshinskii-Moriya interaction (DMI) is an asymmetric exchange interaction that originates from spin-orbit couplings combined with a broken inversion symmetry. Motivated by recent experimental developments, we investigate the effects of DMI strength on spin waves in a 2D lattice spin model with easy-axis anisotropy and an external magnetic field. Furthermore, we consider a setup that consists of a ferromagnetic medium bounded by two metallic reservoirs. We compute the transverse and longitudinal spin current in this setup using the stochastic Landau-Lifshitz-Gilbert equation with appropriate boundary conditions. We find that the transverse spin current vanishes, whereas the longitudinal spin current is influenced by DMI.