Role of spin-orbit coupling in the far infrared absorption of lateral semiconductor dots

TL;DR

This paper explores how spin-orbit coupling influences far-infrared absorption in semiconductor quantum dots, predicting distinctive spectral features and charge-spin distributions that depend on the Dresselhaus interaction strength.

Contribution

It introduces a detailed analysis of spin-orbit effects on absorption spectra and charge-spin distributions in semiconductor dots, including the impact of electron-electron interactions.

Findings

Predicted splittings of the Kohn peak due to spin-orbit coupling

Identified low energy modes with unique charge and spin distributions

Analyzed the robustness of spectral features against electron interactions

Abstract

We investigate the relevance of the spin-orit coupling to the far-infrared absorption of two-dimensional semiconductor dots. Varying the strength of the Dresselhaus term, a mechanism feasible in experiment by changing the dot width, distinctive splittings of the Kohn peak as well as additional low energy modes are predicted in a non-interacting model. Each mode has a spatial distribution of charge, perpendicular and in-plane spin densities that correlate in a peculiar way with the frequency and polarization of the external field. We study the robustness of these features against electron-electron interactions as well as the appearance of interaction-induced additional characteristics.