<i>Ab initio</i> ultrafast spin dynamics in solids

Spin relaxation and decoherence is at the heart of spintronics spin-based quantum information science. Currently, theoretical approaches that can accurately predict spin general solids including necessary scattering pathways capable for ns to ms simulation time are urgently needed. We present a first-principles real-time density-matrix approach based on Lindblad dynamics simulate ultrafast solid-state systems. Through complete descriptions pump, probe processes electron-phonon, electron-impurity electron-electron scatterings with self-consistent electronic spin-orbit couplings, our method directly pump-probe measurements coupled electron over any temperatures doping levels. first apply this prototypical system GaAs obtain excellent agreement experiments. find relative contributions different mechanisms phonon modes differ considerably between carrier processes. In sharp contrast previous work model Hamiltonians, we point out negligible room temperature but becomes dominant low in n-type GaAs. further examine novel spin-valleytronic materials - monolayer bilayer WSe2 realistic defects. highly sensitive local symmetry chemical bonds around Our provides predictive computational platform solids, which has unprecedented potentials designing new ideal technology.