# Non-linear Magnetoresistance Oscillations in Intensely Irradiated Two-Dimensional Electron Systems Induced by Multi-Photon Processes

## TL;DR

This study investigates nonlinear magnetoresistance oscillations in 2D electron systems caused by intense microwave radiation, highlighting multi-photon processes and providing a model to determine microwave intensity.

## Contribution

It introduces a quantum kinetic model explaining nonlinear oscillations due to multi-photon processes at high microwave power in 2D electron systems.

## Key findings

- Oscillations depend on microwave frequency and intensity.
- Theoretical model accurately describes observed phenomena.
- Method to determine microwave intensity on electrons.

## Abstract

We report on magneto-oscillations in differential resistivity of a two-dimensional electron system subject to intense microwave radiation. The period of these oscillations is determined not only by microwave frequency but also by its intensity. A theoretical model based on quantum kinetics at high microwave power captures all important characteristics of this phenomenon which is strongly nonlinear in microwave intensity. Our results demonstrate a crucial role of the multi-photon processes near the cyclotron resonance and its harmonics in the presence of strong dc electric field and offer a unique way to reliably determine the intensity of microwaves acting on electrons.