Non-linear transport in high-mobility 2D electron gas in very high Landau levels under sub-GHz excitation

Microwave-induced resistance oscillations (MIROs) occur when a 2D electron or hole gas is subjected to microwave radiation and weak magnetic field (B), such that the cyclotron frequency is smaller than the radiation frequency. Here, we report on experiments in the opposite limit, in which the cyclotron frequency greatly exceeds the frequency of radiation. In this regime, our measurements reveal another class of photo-resistance oscillations which, like MIROs, are periodic in 1/B. However, unlike MIROs, whose period is governed by the radiation frequency, the period of the oscillations under study is controlled by the radiation intensity.