Journal of Communications Technology and Electronics

Noise equivalent temperature difference of a superconducting integrated terahertz receiver

Roman V. Ozhegov, O. V. Okunev, Gregory N Gol'tsman, Lyudmila V. Filippenko, V. P. Koshelets

Published Jun 1, 2009• 1 citation

Abstract

The dependence of the noise equivalent temperature difference (NETD) of a superconducting integrated receiver (SIR) on the receiver noise temperature and the inputsignal level has been investigated. An unprecedented NETD of 13±2 mK has been measured at a SIR noise temperature of 200 K, intermediate-frequency bandwidth of 4 GHz, and time constant of 1 s. With a decrease in the input signal, an improvement in the NETD is observed. This effect is explained by a reduction in the influence of the instabilities of the receiver power supply and the amplification circuit that occur when the input signal is decreased.

DOI: 10.1134/s1064226909060151

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