Magnetoelastic coupling enabled tunability of magnon spin current generation in two-dimensional antiferromagnets
N. Bazazzadeh, M. Hamdi, S. Park, A. Khavasi, S. M. Mohseni, A. Sadeghi
Abstract
We theoretically investigate the magnetoelastic coupling (MEC) and its effect on magnon transport in two-dimensional antiferromagnets with a honeycomb lattice. MEC coefficients along with magnetic exchange parameters and spring constants are computed for monolayers of transition-metal trichalcogenides with N\'eel magnetic order (${\text{MnPS}}_{3}$ and ${\text{VPS}}_{3}$) and zigzag order (${\text{CrSiTe}}_{3}$, ${\text{NiPS}}_{3}$, and ${\text{NiPSe}}_{3}$) by ab initio calculations. Using these parameters, we predict that the spin-Nernst coefficient is significantly enhanced due to magnetoelastic coupling. Our study shows that although Dzyaloshinskii-Moriya interaction can produce spin-Nernst effect in these materials, other mechanisms such as magnon-phonon coupling should be taken into account. We also demonstrate that the magnetic anisotropy is an important factor for control of magnon-phonon hybridization and enhancement of the Berry curvature and thus the spin-Nernst coefficient. Our results pave the way toward gate tunable spin current generation in two-dimensional magnets by spin-Nernst effect via electric field modulation of MEC and anisotropy.