Magnetotransport in a two-dimensional electron gas in the presence of spin-orbit interaction

TL;DR

This paper investigates how spin-orbit interaction affects magnetotransport in a 2D electron gas, revealing beating patterns, peak splitting, and Hall plateau doubling that relate to the Rashba coupling strength.

Contribution

It provides a theoretical analysis of the impact of Rashba spin-orbit interaction on magnetotransport properties in a 2DEG, linking observable patterns to SOI strength.

Findings

Beating patterns in density of states and resistivity match experimental observations.

Positions of beating nodes estimate Rashba coupling strength.

Strong SOI causes splitting of magnetoresistance peaks and doubles Hall plateaus.

Abstract

We evaluate the transport coefficients of a two-dimensional electron gas (2DEG) in the presence of a perpendicular magnetic field and of the spin-orbit interaction (SOI) described only by the Rashba term. The SOI mixes the spin-up and spin-down states of neighboring Landau levels into two new, unequally spaced energy branches. The broadened density of states, as a function of the energy, and the longitudinal resistivity, as a function of the magnetic field, show beating patterns in agreement with observations. The positions of any two successive nodes in the beating pattern approximately determine the strength of the Rashba term. A strong SOI results in a splitting of the magnetoresistance peaks and a doubling of the number of the Hall plateaus. The peak value in derivative of the Hall resistivity reflects the strength of the SOI.