Spin and orbital Edelstein effect in an oxide two-dimensional electron gas: theory and application to AlO$_x$/SrTiO$_{3}$

TL;DR

This paper investigates the Edelstein effect in an oxide 2DEG at the SrTiO$_3$/AlO interface, revealing that orbital contributions dominate spin responses, with implications for electrically controlling magnetization.

Contribution

It provides a theoretical analysis showing orbital Edelstein effect surpasses spin effect in a specific oxide 2DEG system, highlighting the importance of orbital moments.

Findings

Orbital Edelstein effect exceeds spin Edelstein effect by over an order of magnitude.

Orbital moments in Rashba-like band pairs are key to the effect's strength.

The study combines theory with potential applications in oxide electronics.

Abstract

The Edelstein effect provides the purely electrical generation and control of a homogeneous magnetization in primarily nonmagnetic materials with broken inversion symmetry. Usually, only the spin density response to an external electric field is discussed. Here, we report on the electrically induced magnetization containing spin as well as orbital contributions in the topological oxide two-dimensional electron gas at the interface between SrTiO$_3$ and AlO. We find that in this particular system the orbital Edelstein effect exceeds the spin Edelstein effect by more than one order of magnitude. The main reason are orbital moments of different magnitude in the Rashba-like-split band pairs.