Terahertz responsivity of AlGaN/GaN bow-tie diode detectors at the temperatures of 295 K and 80 K

terahertz (THz) responsivity of the planar bow-tie (BT) diodes based on AlGaN/GaN high electron mobility transistor (HEMT) structures were investigated at the temperatures of 295 K and 80 K in the frequency range of 150-600 GHz. At 295 K, the zero-bias responsivity of the BT diode was found to be of about 72 mV/W. Biasing the detector by $\pm 1V$ allowed us to increase the responsivity by at least 50 times, while cooling the detectors down to 80 K demonstrated the increase by up to 20 times independently on the frequency of THz beam.