Multi-Photon Transitions in Coupled Plasmon-Cyclotron Resonance Measured by Millimeter-Wave Reflection

TL;DR

This paper introduces a nondestructive microwave interferometry method to measure high-frequency properties of 2DEGs, revealing multi-photon PCR phenomena relevant to microwave-induced resistance oscillations.

Contribution

The authors develop a low-temperature microwave waveguide interferometer that enables high-sensitivity, nondestructive measurement of coupled plasmon-cyclotron resonance in 2DEGs without sample preparation.

Findings

PCR signals resolved at microwave power as low as 10 nW

Observation of multi-photon transition regime in PCR

Correlation of PCR spectra with microwave-induced resistance oscillations

Abstract

We construct a low-temperature microwave waveguide interferometer for measuring high-frequency properties of two-dimensional electron gases (2DEGs). Coupled plasmon-cyclotron resonance (PCR) spectra are used to extract effective mass, bulk plasmon frequency, and carrier relaxation times. In contrast to traditional transmission spectroscopy, this method does not require sample preparation and is nondestructive. PCR signals can be resolved with a microwave power source as low as 10 nW. We observe PCR in the multi-photon transition regime, which has been proposed to be relevant to the microwave-induced resistance oscillations.