Terahertz detection by two dimensional plasma field effect transistors in quantizing magnetic fields

Detection of terahertz radiation by two dimensional electron plasma in high electron mobility GaAs/GaAlAs transistors was investigated at cryogenic temperatures in quantizing magnetic fields. Shubnikov-de Haas oscillations of the detection signal were observed. A double (optical and electrical) modulation technique applied allowed us to study the influence of gated and ungated parts of the transistor channel on the detection. Our results provide a direct experimental evidence that both the gated and ungated plasma participate in the detection and clearly show the necessity to improve theoretical models that usually take into account only the gated part of the channel.