Microwave-induced resistance oscillations and zero-resistance states in 2D electron systems with two occupied subbands

TL;DR

This paper presents a theoretical analysis of microwave-induced resistance oscillations and zero-resistance states in 2D electron systems with two subbands, revealing interference effects and matching experimental observations.

Contribution

It introduces a model explaining the interference effects in resistance oscillations due to intra- and inter-subband scattering in two-subband 2D electron systems.

Findings

Resistance exhibits interference effects not previously observed.

Calculated oscillation frequencies differ for the two subbands.

Results agree well with experimental data.

Abstract

We report on theoretical studies of recently discovered microwave-induced resistance oscillations and zero resistance states in Hall bars with two occupied subbands. In the same results, resistance presents a peculiar shape which appears to have a built-in interference effect not observed before. We apply the microwave-driven electron orbit model, which implies a radiation-driven oscillation of the two-dimensional electron system. Thus, we calculate different intra and inter-subband electron scattering rates and times that are revealing as different microwave-driven oscillations frequencies for the two electronic subbands. Through scattering, these subband-dependent oscillation motions interfere giving rise to a striking resistance profile. We also study the dependence of irradiated magnetoresistance with power and temperature. Calculated results are in good agreement with experiments.