Out-of-plane spin polarization from in-plane electric and magnetic fields

TL;DR

This paper demonstrates that combined spin-orbit and magnetic fields can induce out-of-plane spin polarization in 2D electron systems with Rashba coupling, aligning with experimental observations.

Contribution

It introduces a theoretical model showing out-of-plane spin polarization due to combined fields, extending understanding beyond simplified models.

Findings

Out-of-plane polarization occurs with angle-dependent scattering or nonparabolic spectra.

Derived Bloch equations match experimental static and dynamic responses.

Magnetic field influences the spin polarization behavior.

Abstract

We show that the joint effect of spin-orbit and magnetic fields leads to a spin polarization perpendicular to the plane of a two-dimensional electron system with Rashba spin-orbit coupling and in-plane parallel dc magnetic and electric fields, for angle-dependent impurity scattering or nonparabolic energy spectrum, while only in-plane polarization persists for simplified models. We derive Bloch equations, describing the main features of recent experiments, including the magnetic field dependence of static and dynamic responses.