Linear polarization study of microwave-radiation-induced magnetoresistance oscillations: Comparison of power dependence to theory

TL;DR

This paper investigates how microwave power and polarization angle affect magnetoresistance oscillations in high-mobility 2D electron systems, revealing sinusoidal and harmonic behaviors and proposing a theory to explain these phenomena.

Contribution

It provides the first detailed experimental analysis of polarization angle dependence at varying microwave powers and introduces a new theoretical explanation for observed behaviors.

Findings

Magnetoresistance oscillations depend sinusoidally on polarization angle.

Higher microwave power introduces harmonic content in angular dependence.

Theoretical model explains the transition to cosine-like behavior.

Abstract

We present an experimental study of the microwave power and the linear polarization angle dependence of the microwave-induced magnetoresistance oscillations in the high-mobility GaAs/AlGaAs two-dimensional electron system. Experimental results show the sinusoidal dependence of the oscillatory magnetoresistance extrema as a function of the polarization angle. Yet, as the microwave power increases, the angular dependence includes additional harmonic content, and it begins to resemble the absolute value of the cosine function. We present a theory to explain such peculiar behavior.