Dynamic Rashba-Dresselhaus Effect.

The relativistic interaction between the spin of an electron and its orbit in a solid is key to understanding novel phenomena in condensed matter physics, such as topologically-protected states, spin-orbit torques, and Majorana modes. Here we focus on the prototypical spin-orbit coupling process, the Rashba-Dresselhaus effect, and analyze how it is modified by lattice vibrations. We show that, in centrosymmetric non-magnetic crystals, dynamic spin splitting is symmetry-forbidden in thermodynamic equilibrium, but it is allowed in crystals with an out-of-equilibrium phonon population. Our findings resolve the current debate on the possibility of phonon-induced Rashba-Dresselhaus effects, reconcile conflicting experimental and theoretical evidence on the Rashba-Dresselhaus effect in hybrid perovskites, and establish the design principles for engineering spin texture in quantum matter via coherent phonons.