High power terahertz emission from a single gate AlGaN/GaN field effect transistor with periodic Ohmic contacts for plasmon coupling

We report on room temperature terahertz (THz) emission by a single, short gate AlGaN/GaN field effect transistor with grating Ohmic contacts. The fingers of metal contacts are fabricated at the nanoscale in length and spacing in order to work as a radiation coupler of electron plasmons in the THz range. Spectrum analysis revealed a broadband emission centered at 1.5 THz with a controlled polarization by the grating contacts. The measured output power is linearly increased with the drain input power and reached up to 1.8 mu W. (C) 2010 American Institute of Physics. [doi:10.1063/1.3486473]