Spin dynamics in a spin-orbit coupled Fermi gas

Abstract

We study the dynamics of a non-degenerate, harmonically trapped Fermi gas following a sudden ramp of the spin-orbit coupling strength. In the non-interacting limit, we solve the Boltzmann equation in the presence of spin orbit coupling analytically, and derive expressions for the dynamics of an arbitrary initial spin state. In particular we show that for a fully spin polarized initial state, the total magnetization exhibits collapse and revival dynamics in time with a period set by the trapping potential. In real space, this corresponds to oscillations between a fully polarized state and a spin helix. We numerically study the effect of interactions on the dynamics using a collisionless Boltzmann equation.

8 pages, 3 figures Expanded to include discussion of dynamics in the presence of a Zeeman field, rewritten section with interactions