Physics Procedia

Spectral Response and Noise Temperature of a 2.5 THz Spiral Antenna Coupled NbN HEB Mixer

Wen Zhang, W. Miao, Qi Yao, Zichao Lin, S. C. Shi, J. R. Gao, G. N. Gol'tsman

Published Jan 1, 2012• 7 citations

Abstract

We report on a 2.5 THz spiral antenna coupled NbN hot electron bolometer (HEB) mixers, fabricated with in-situ process. The receiver noise temperature with lowest value of 1180 K is in good agreement with calculated quantum efficiency factor as a function of bias voltage. In addition, the measured spectral response of the spiral antenna coupled NbN HEB mixer shows broad frequency coverage of 0.8-3 THz, and corrected response for optical losses, FTS, and coupling efficiency between antenna and bolometer falls with frequency due to diffraction-limited beam of lens/antenna combination.

DOI: 10.1016/j.phpro.2012.06.169

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