https://phys.org/news/2019-07-light-sensing-distant-galaxies-unprecedented.html Light-sensing system could show distant galaxies in unprecedented detail: Researchers at the UCLA Samueli School of Engineering have developed an ultra-sensitive light-detecting system that could enable astronomers to view galaxies, stars and planetary systems in superb detail. The system works at room temperature—an improvement over similar technology that only works in temperatures nearing 270 degrees below zero Celsius, or minus 454 degrees Fahrenheit. A paper detailing the advance is published today in Nature Astronomy. The sensor system detects radiation in the terahertz band of the electromagnetic spectrum, which includes parts of the far-infrared and microwave frequencies. more at link..... the paper: https://www.nature.com/articles/s41550-019-0828-6 Room-temperature heterodyne terahertz detection with quantum-level sensitivity Abstract: Our Universe is most radiant at terahertz frequencies (0.1–10.0 THz) (ref. 1), providing critical information on the formation of the planets, stars and galaxies, as well as the atmospheric constituents of the planets, their moons, comets and asteroids2,3,4,5,6,7,8,9. The detection of faint fluxes of photons at terahertz frequencies is crucial for many planetary, cosmological and astrophysical studies10,11,12,13,14. For example, understanding the physics and molecular chemistry of the life cycle of stars and their relationship with the interstellar medium in galaxies requires heterodyne detectors with noise temperatures close to the quantum limit15. Near-quantum-limited heterodyne terahertz detection has so far been possible only through the use of cryogenically cooled superconducting mixers as frequency downconverters15,16,17,18. Here we introduce a heterodyne terahertz detection scheme that uses plasmonic photomixing for frequency downconversion to offer quantum-level sensitivities at room temperature. Frequency downconversion is achieved by mixing terahertz radiation and a heterodyning optical beam with a terahertz beat frequency in a plasmonics-enhanced semiconductor active region. We demonstrate terahertz detection sensitivities down to three times the quantum limit at room temperature. With a versatile design capable of broadband operation over a 0.1–5.0 THz bandwidth, this plasmonic photomixer has broad applicability to astronomy, cosmology, atmospheric studies, gas sensing and quantum optics.