Low Noise Receivers Using Niobium Nitride Hot Electron Bolometer Mixers from 0.76 to 3.1 THz

J. Chen, Min Liang, Lin Kang, Biao Jin, Weiwei Xu, Pan Wu, W. Zhang, Ling Jiang

Published Jan 1, 2009• 1 citation

Abstract

Low noise receivers using quasi-optical superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixers have been designed, fabricated and measured in the terahertz (THz) frequency range for THz applications in astronomy and cosmology. The NbN HEB mixers consist of a planar complementary antenna and several nanometer (nm) thick NbN bridge connecting across the antenna's inner terminals on high-resistivity Si substrates. A double sideband (DSB) receiver noise temperature of 664 K at 0.76 THz, 920 K at 1.6 THz, 1630 K at 2.5 THz and 1710 K at 3.1 THz has been obtained without corrections and no anti-reflection (AR) coating on the surface of the lens.

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