Anharmonic behavior in Microwave-driven resistivity oscillations in Hall bars

TL;DR

This paper investigates the anharmonic behavior in microwave-driven resistivity oscillations in 2D electron systems under high-intensity, low-frequency radiation, revealing distorted oscillations and subharmonic resonance peaks.

Contribution

It demonstrates how high microwave intensity induces anharmonic electron orbit motion, explaining new features in magnetoresistivity responses.

Findings

Observation of distorted oscillations in magnetoresistivity

Detection of new resonance peaks at subharmonics

Correlation between microwave intensity and anharmonic effects

Abstract

We analyzed the magnetoresistivity of a two-dimensional electron system excited by microwave radiation in a regime of high intensities and low frequencies. In such a regime, recent experiments show that different features appear in the magnetoresistivity response which suggest an anharmonic behavior. These features consist mainly in distorted oscillations and new resonance peaks at the subharmonics of the cyclotron frequency. We follow the model of microwave-driven electron orbits motion which become anharmonic when the ratio of microwave intensity to microwave frequency is large enough.