Superconductivity

Superconducting hot-electron bolometer mixers and their applications

Wen Zhang, Wei Miao, Yuan Ren, Kangmin Zhou, Sheng‐Cai Shi

Published May 8, 2022• 17 citations

Abstract

Superconducting hot electron bolometer (HEB) mixers are the most sensitive heterodyne detectors at frequencies beyond 1 THz, and are used for many astronomical observations. HEB, consisting of a narrow and short superconducting thin film patch connected to an antenna via contact pads, is brought into a highly sensitive operating regime by applying a DC current and a certain amount of local-oscillator power. Potentially, superconducting HEB mixers are capable of exhibiting high sensitivity for frequencies up to several tens of THz, as their output noise and conversion gain are nearly frequency independent according to the mixing mechanism. Moreover, the understanding of mixing mechanism has evolved over time from lumped-element model to distributed hot-spot model. In this review, we provide an overview of theoretical and experimental studies on HEBs and their applications, especially in astronomical observations on ground, airborne and space telescopes.

DOI: 10.1016/j.supcon.2022.100009

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