Application of Superconducting Hot-Electron Bolometer Mixers for Terahertz-Band Astronomy

Recently, a next-generation heterodyne mixer detector— a hot electron bolometer (HEB) mixer employing a superconducting microbridge—has gradually opened up terahertz-band astronomy. The surrounding state-of-the-art technologies including fabrication processes, 4 K cryostats, cryogenic low-noise amplifiers, local oscillator sources, micromachining techniques, and spectrometers, as well as the HEB mixers, have played a valuable role in the development of super-low-noise heterodyne spectroscopy systems for the terahertz band. The current developmental status of terahertz-band HEB mixer receivers and their applications for spectroscopy and astronomy with ground-based, airborne, and satellite telescopes are presented. key words: superconducting hot-electron bolometer mixer receiver, astrophysics, heterodyne spectroscopy, terahertz