Quasioptical NbN Phonon-Cooled Hot Electron Bolometric Mixers with Low Optimal Local Oscillator Power
Pavel A. Yagoubov, M. Kroug, H. Merkel, E. Kollberg, G. N. Gol'tsman, Andrey P. Lipatov, S. Svechnikov, E. Gershenzon
Abstract
In this paper, the noise perform.ance of NIN based phonon-cooled Hot Electron Bolometric (HEB) quasioptical mixers is investigated in the 0.55-1.1 THz frequency range. The best results of the DSB noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz. The water vapor in the signal path causes a significant contribution to the measured noise temperature around 1.1 THz. The required LO power is typically about 60 nW. The frequency response of the spiral antenna+lens system is measured using a Fourier Transform Spectrometer with the HEB operating in a detector mode.