Theory of the inverse spin galvanic effect in quantum wells

TL;DR

This paper develops a theoretical framework for understanding the inverse spin galvanic effect in quantum wells, highlighting the role of cubic spin-orbit coupling terms in explaining experimental observations and advancing spintronics applications.

Contribution

It introduces a comprehensive theory including cubic spin-orbit terms to explain the inverse spin galvanic effect in quantum wells, challenging previous assumptions.

Findings

Cubic spin-orbit terms qualitatively explain experimental CISP results.

Inversion of spin polarization depends on the strength of internal spin-orbit fields.

Provides a framework for controlling spin transport in spintronics devices.

Abstract

The understanding of the fundamentals of spin and charge densities and currents interconversion by spin-orbit coupling can enable efficient applications beyond the possibilities offered by conventional electronics. For this purpose we consider various forms of the frequency-dependent inverse spin galvanic effect (ISGE) in semiconductor quantum wells and epilayers taking into account the cubic in the electron momentum spin-orbit coupling in the Rashba and Dresselhaus forms, concentrating on the current-induced spin polarization (CISP). We find that including the cubic terms qualitatively explains recent findings of the CISP in InGaAs epilayers being the strongest if the internal spin-orbit coupling field is the smallest and vice versa (Norman et . 2014, Luengo et al. 2017), in contrast to the common understanding. Our results provide a promising framework for the control of spin transport in future spintronics devices.