Chirality and intrinsic dissipation of spin modes in two-dimensional electron liquids

TL;DR

This review discusses recent advances in understanding collective spin excitations in two-dimensional electron liquids, emphasizing the roles of many-body interactions, spin-orbit coupling, and intrinsic dissipation, with implications for spintronics and emerging 2D materials.

Contribution

It synthesizes recent theoretical and experimental findings on chiral effects and dissipation in 2DEL spin modes, highlighting new insights and future directions in the field.

Findings

Identification of chiral effects in spin modes

Analysis of intrinsic dissipation mechanisms

Implications for spintronics applications

Abstract

We review recent theoretical and experimental developments concerning collective spin excitations in two-dimensional electron liquid (2DEL) systems, with particular emphasis on the interplay between many-body and spin-orbit effects, as well as the intrinsic dissipation due to the spin-Coulomb drag. Historically, the experimental realization of 2DELs in silicon inversion layers in the 60s and 70s created unprecedented opportunities to probe subtle quantum effects, culminating in the discovery of the quantum Hall effect. In the following years, high quality 2DELs were obtained in doped quantum wells made in typical semiconductors like GaAs or CdTe. These systems became important test beds for quantum many-body effects due to Coulomb interaction, spin dynamics, spin-orbit coupling, effects of applied magnetic fields, as well as dissipation mechanisms. Here we focus on the recent results involving chiral effects and intrinsic dissipation of collective spin modes: these are not only of fundamental interest but also important towards demonstrating new concepts in spintronics. Moreover, new realizations of 2DELs are emerging beyond traditional semiconductors, for instance in multilayer graphene, oxide interfaces, dichalcogenide monolayers, and many more. The concepts discussed in this review will be relevant also for these emerging systems.