Ultrafast superconducting single-photon optical detectors and their applications

Superconducting detectors become the most prominent technology for radiation sensors with ultimate performance. Typically, they are nanostructures formed from an ultra-thin superconducting film incorporated into an external antenna for efficient radiation coupling. The operation of so-called hot-electron bolometers and photodetectors (HEBs and HEPs) is based on nonequilibrium heating of the electron subsystem by the absorbed radiation and results in the film resistance and a corresponding, easily measurable voltage response when device is current biased [1-2]. A relatively simple, single-layer manufacturing technology made these devices very popular for needs of radioastronomy and remote sensing.