Linear polarization dependence of microwave-induced magnetoresistance oscillations in high-mobility two-dimensional systems

TL;DR

This study investigates how the linear polarization angle of microwaves affects magnetoresistance oscillations in high-mobility 2D systems, revealing sinusoidal amplitude variations and explaining previous experimental results.

Contribution

It provides a theoretical analysis of polarization dependence in microwave-induced magnetoresistance oscillations, aligning with and explaining prior experimental findings.

Findings

Magnetoresistance oscillation amplitude varies sinusoidally with polarization angle.

Maximum oscillation amplitude occurs at a nonzero polarization angle.

Results explain previous experimental observations by Mani and Ramanayaka.

Abstract

We examine the effect of changing the linear polarization angle $\theta$ of incident microwaves with respect to the dc current on radiation-induced magnetoresistance oscillations in a two-dimensional (2D) system within the balance-equation formulation of the photon-assisted magnetotransport model, considering the radiative decay as the sole damping mechanism. At an extremum the amplitude of oscillatory magnetoresistance $R_{xx}$ exhibits a sinusoidal, up to a factor of 5, magnitude variation with rotating the polarization angle $\theta$. The maximal amplitude shows up generally at a nonzero $\theta$, which is dependent upon the extremum in question, the 2D electron setup, the radiation frequency and the magnetic field orientation. These results provide a natural explanation for the experimental observations by Mani {\it et al.} [Phys. Rev. B {\bf 84}, 085308 (2011)], and Ramanayaka {\it et al.} [Phys. Rev. B {\bf 85}, 205315 (2012)].