Emission of terahertz radiation from an interdigitated grating gates high electron-mobility transistors

New doubly interdigitated grating gate high- electron mobility transistor (HEMT) was illuminated at room temperature by a 1.5-mum CW laser. A clear emission of the terahertz radiation has been detected using a Silicon bolometer cooled down to 4.2 K and placed in the front of the sample. The observed signal was related to the self oscillation of the plasma waves in our new HEMT device.