Multiphoton microwave photoresistance in a high-mobility two-dimensional electron gas

TL;DR

This study investigates microwave-induced resistance oscillations in a high-mobility two-dimensional electron gas, revealing a transition from linear to sublinear power dependence and highlighting the importance of multiphoton processes at high microwave intensities.

Contribution

The paper introduces a quantum kinetic theory that explains the crossover in power dependence of resistance oscillations at high microwave intensities.

Findings

Observation of crossover from linear to sublinear power dependence

Narrowing of oscillation extrema at high microwave intensities

Demonstration of multiphoton processes' role in resistance oscillations

Abstract

We report on experimental and theoretical studies of microwave-induced resistance oscillations in a two-dimensional electron gas over a wide range of microwave intensities. We observe a distinct crossover from linear to sublinear power dependence of the oscillation amplitude and a concomitant narrowing of the oscillation extrema. To explain our observations we propose a theory based on the quantum kinetic equation at arbitrary microwave power. Taken together, these findings demonstrate a crucial role of multiphoton processes at elevated microwave intensities.