Two-dimensional electron systems (2DES) formed in semiconductor heterostructures host a rich variety of transport phenomena. At low magnetic field, irradiated heterostructures reveal microwave-induced resistance oscillations (MIRO) and associated zero-resistance state. In this talk, I will give an overview on the main transport phenomena occurring in 2DES when it is driven by microwave and then discuss our recent findings. First, we study the effect of low-temperature illumination employed MIRO, which results in a great improvement on magnetotransport quality. Second, we observe the beating pattern in MIRO with flipped phase at high harmonics. I'll discuss how its origin is identified as from an in-plane built-in electric field across the 2DES, suggesting that the doping layer of quantum well might play an essential role.
FU Xiaojun received her bachelor's degree from USTC in 2015 and she is now a graduate student in physics at University of Minnesota. She is working on magnetotransport in quantum Hall systems at low temperature, including stripe and bubble phases at high magnetic field, and nonequilibrium transport under microwave and/or dc field at low magnetic field.