Classical and quantum chaotic angular-momentum pumps

TL;DR

This paper investigates how classical and quantum chaotic scattering with spin-orbit coupling can generate polarized charge and spin currents through a periodically driven system, combining theoretical analysis and numerical simulations.

Contribution

It introduces a novel mechanism for spin and charge pumping using chaotic scattering with spin-orbit coupling and confirms it with quantum Floquet analysis and numerical solutions.

Findings

Chaotic scattering induces spin flips and polarized currents.

Spin pumping mechanisms are valid at quantum level.

Numerical simulations support the theoretical model.

Abstract

We study directed transport of charge and intrinsic angular momentum by periodically driven scattering in the regime of fast and strong driving. A spin-orbit coupling through a kicked magnetic field confined to a compact region in space leads to irregular scattering and triggers spin flips in a spatially asymmetric manner which allows to generate polarized currents. The dynamical mechanisms responsible for the spin separation carry over to the quantum level and give rise to spin pumping. Our theory, based on the Floquet formalism, is confirmed by numerical solutions of the time-dependent inhomogeneous Schr\"{o}dinger equation with a continuous source term.