THz Emission Induced by an Optical Beating in Nanometer-Length High-Electron-Mobility Transistors

Experimental results of direct measurement of resonant terahertz emission optically excited in InGaAs HEMT channels are presented.The emission was attributed to two-dimensional plasma waves excited by photogeneration of electron-hole pairs in the HEMT channel at the frequency of the beating of two cw-laser sources.The presence of resonances for the radiation emission in the range of f 0 ± 10 GHz (with f 0 from 0.3 up to 0.5 THz) detected by a Si--bolometer is found.The intensity of THz emission exhibits a nonlinear growth with increase of the pumping power.