Cyclotron-resonance-induced photovoltage of inversion electrons on GaAs

We report a novel photovoltaic response occurring in gated AlAs-GaAs heterojunctions whenever inversion electrons absorb far-infrared radiation at cyclotron resonance. With radiation intensities below 1 mW/${\mathrm{cm}}^2$, photovoltages up to several mV are observed with the strongest signals around even Landau-level filling factors. The experiment can be described within the framework of carrier heating caused by resonantly absorbed far-infrared radiation. We present a simple model demonstrating that the photovoltage can be understood as reflecting the difference in the inversion electron chemical potentials at two different electron temperatures.