Terahertz Radiation Detection by Field Effect Transistor in Magnetic Field

We report on terahertz radiation detection with InGaAs/InAlAs field effect transistors in quantizing magnetic field. The photovoltaic detection signal was investigated as a function of the gate voltage and magnetic field. Oscillations analogous to Shubnikov–de Haas oscillations as well as their strong enhancement at the cyclotron resonance were observed. The results are quantitatively described by a recent theory, showing that the detection is due to rectification of the terahertz radiation by plasma waves related nonlinearities in the gated part of the channel.