Microwave Photoresistance in dc-driven 2D Systems at Cyclotron Resonance Subharmonics

TL;DR

This study investigates microwave-induced photoresistivity oscillations in high mobility 2D electron systems under strong dc electric fields, revealing a doubled oscillation frequency near the second cyclotron resonance subharmonic due to microwave-induced sidebands.

Contribution

It uncovers a novel doubling of oscillation frequency near the second cyclotron resonance subharmonic, linked to microwave-induced sidebands and scattering processes in Landau levels.

Findings

Oscillation frequency doubles near the second subharmonic of cyclotron resonance.

Microwave-induced sidebands influence the density of states.

Interplay of scattering processes affects photoresistivity oscillations.

Abstract

We study microwave photoresistivity oscillations in a high mobility two-dimensional electron system subject to strong dc electric fields. We find that near the second subharmonic of the cyclotron resonance the frequency of the resistivity oscillations with dc electric field is twice the frequency of the oscillations at the cyclotron resonance, its harmonics, or in the absence of microwave radiation. This observation is discussed in terms of the microwave-induced sidebands in the density of states and the interplay between different scattering processes in the separated Landau level regime.