First principles analysis of phonon-induced spin-orbit torques

In the presence of spin-orbit coupling, lattice vibrations in materials generate a dynamic magnetic field that exerts a torque on the electron's angular momentum. This spin-orbit torque contributes to microscopic relaxation processes of electron spins, and its understanding is important for designing materials for spintronics and spin-based quantum technologies. In this talk, we show a first principles framework for quantitative calculations of phonon-induced spin-orbit torques. We then apply this method to study several materials with and without inversion symmetry. Comparing the electron-phonon interaction with the phonon-induced torques reveals significant differences between the coupling of phonon modes with charge and spin, and provides new insights into the role of material symmetry on spin relaxation. This work provides a robust methodology for quantifying phonon-induced torques, advancing our understanding of microscopic spin dynamics.