Effect of microwave radiation on non-linear resistivity of a two-dimensional electron gas at large filling factors

TL;DR

This paper investigates how microwave radiation influences the non-linear resistivity of a two-dimensional electron gas under strong magnetic fields, revealing oscillatory behavior of electric current consistent with experimental observations.

Contribution

It provides a unified quantum Boltzmann framework to analyze non-equilibrium electron distributions and scattering modifications under microwave irradiation in disordered 2D electron gases.

Findings

Electric current oscillates with microwave frequency and field strength.

Theoretical results qualitatively match experimental data.

Both non-equilibrium distribution and scattering modifications are crucial.

Abstract

We study transport properties of a two-dimensional electron gas, placed in a classically strong perpendicular magnetic field and in constant and oscillating in-plane electric fields. The analysis is based on a quantum Boltzmann equation derived for a weakly disordered two-dimensional electron gas. We consider disordered potential with both long and short range correlations. Electron scattering off such disorder is not limited to small change in momentum direction, but occurs on an arbitrary angle, including the backscattering. The non-linearity of the transport in the considered system is a consequence of two co-existing effects: formation of a non-equilibrium distribution function of electrons and modification of the scattering rate off the disorder in the presence of dc and ac electric fields. This work describes both effects in a unified way. The calculated dissipative component of electric current oscillates as a function of the electric field strength and frequency of microwave radiation in a qualitative agreement with experiments.