Hall Conductance of a Two-Dimensional Electron Gas with Spin-Orbit Coupling at the Presence of Lateral Periodic Potential

TL;DR

This paper investigates how spin-orbit coupling and periodic potentials influence the Hall conductance distribution in a two-dimensional electron gas under magnetic fields, revealing deviations from traditional quantization laws.

Contribution

It provides a detailed analysis of Hall conductance distribution in systems with Rashba spin-orbit coupling, highlighting the effects of system parameters and subband interactions.

Findings

Hall conductance distribution depends on system parameters and subband interactions.

Strong spin-orbit coupling causes deviations from traditional quantization laws.

Decreasing lattice period and subband touching drastically alter conductance distribution.

Abstract

We evaluate the distribution of Hall conductances in magnetic subbands of two-dimensional electron gas with Rashba spin-orbit (SO) coupling placed in a periodic potential and perpendicular magnetic field. In this semiconductor structure the spin-orbit coupling mixes the states of different magnetic subbands and changes the distribution of their Hall conductances in comparison with the case of spinless particles. The calculations were made for semiconductor structures with a weak ($AlGaAs/GaAs$) and relatively strong ($GaAs/InGaAs$) SO and Zeeman interactions. The Hall conductances of fully occupied magnetic subbands depend on the system parameters and can be changed when neighboring subbands touch each other. It was shown that in the real semiconductor structures with relatively strong SO coupling the distribution of Hall conductance differs from the quantization law predicted by Thouless et al\cite{Thoul} for systems without spin-orbit coupling. In the case of weak SO interaction and relatively large lattice period the Hall conductance of magnetic subbands are the same as for spinless particles, but as the lattice period decreases and two neighboring subbands touch each other the distribution of Hall conductances is changed drastically.