Microwave Photoconductivity in Two-Dimensional Electron Systems due to Photon-Assisted Interaction of Electrons with Leaky Interface Phonons

TL;DR

This paper investigates how microwave radiation interacting with leaky interface phonons affects the electrical conductivity in 2D electron systems, revealing oscillations and conditions for negative conductivity.

Contribution

It introduces a calculation of photon-assisted electron-phonon interactions' impact on photoconductivity, highlighting differences from impurity interactions and conditions for negative conductivity.

Findings

Photoconductivity exhibits pronounced oscillations with microwave frequency and magnetic field.

The mechanism can lead to absolute negative conductivity under certain conditions.

Distinct oscillation patterns compared to impurity-assisted interactions.

Abstract

We calculate the contribution of the photon-assisted interaction of electrons with leaky interface phonons to the dissipative dc photoconductivity of a two-dimensional electron system in a magnetic field. The calculated photoconductivity as a function of the frequency of microwave radiation and the magnetic field exhibits pronounced oscillations. The obtained oscillation structure is different from that in the case of photon-assisted interaction with impurities. We demonstrate that at a sufficiently strong microwave radiation in the certain ranges of its frequency (or in certain ranges of the magnetic field) this mechanism can result in the absolute negative conductivity.