Heterodyne and subharmonic mixing at 0.6THz in an AlGaAs/InGaAs/AlGaAs heterostructure field effect transistor

We fabricated a two-dimensional-electron-gas field effect transistor with an asymmetric terahertz antenna connected to the channel terminals and a gate length of 1 lm. We investigated frequency mixing in the transistor's channel by measuring, with a quasi-optical setup, the heterodyne, secondand third-order subharmonic mixing signal at 0.592 THz. The dependence on the gate voltage and on the radiation power of both the local-oscillator and the radio-frequency signals was studied for all mixing orders. The conditions for full-plasmonic-mixing are fulfilled in our transistor at room temperature.