Surface acoustic wave induced magnetoresistance oscillations in a 2D electron gas

TL;DR

This paper investigates how surface acoustic waves influence magnetoresistance oscillations in a 2D electron gas, revealing classical and quantum effects, and predicts zero-resistance states at high SAW amplitudes.

Contribution

It provides a theoretical analysis of SAW-induced magnetoresistance oscillations, including the interplay of classical and quantum effects, and predicts zero-resistance states at large SAW amplitudes.

Findings

Classical anisotropic increase in resistivity due to SAW

Quantum isotropic decrease in resistivity from non-equilibrium effects

Prediction of zero-resistance states at high SAW amplitudes

Abstract

We study the geometrical commensurability oscillations imposed onto the resistivity of 2D electrons in a perpendicular magnetic field by a propagating surface acoustic wave (SAW). We show that, for $\omega <\omega_{c}$, this effect is composed of an anisotropic dynamical classical contribution increasing the resistivity and the non-equilibrium quantum contribution isotropically decreasing resistivity, and we predict the appearance of zero-resistance states associated with geometrical commensurability at large SAW amplitude. We also describe how the commensurability oscillations modulate the resonances in the SAW-induced resistivity at multiples of the cyclotron frequency.