Oscillatory ac- and photoconductivity of a 2D electron gas: Quasiclassical transport beyond the Boltzmann equation

TL;DR

This paper investigates the quasiclassical mechanisms behind magnetooscillations in ac- and photoconductivity of a 2D electron gas, highlighting the dominant effect in ac conductivity and proposing a method to measure Landau level broadening.

Contribution

It introduces a non-Markovian quasiclassical approach to analyze magnetooscillations beyond the Boltzmann equation, emphasizing the stronger oscillations in ac conductivity.

Findings

Magnetooscillations are more prominent in ac conductivity than in photoconductivity.

Damping of photoconductivity oscillations can measure Landau level broadening.

Non-Markovian dynamics significantly influence electron scattering effects.

Abstract

We have analyzed the quasiclassical mechanism of magnetooscillations in the ac- and photoconductivity, related to non-Markovian dynamics of disorder-induced electron scattering. While the magnetooscillations in the photoconductivity are found to be weak, the effect manifests itself much more strongly in the ac conductivity, where it may easily dominate over the oscillations due to the Landau quantization. We argue that the damping of the oscillatory photoconductivity provides a reliable method of measuring the homogeneous broadening of Landau levels (single-particle scattering rate) in high-mobility structures.