Superconducting single photon detector

A photon detector for detecting one or more photons from a light source, the photon detector comprising:

• a superconducting film coupled with a substrate, said substrate defines a first side and an opposite second side, said first side having an antireflective coating, and said second side having said superconducting film deposited thereon;
• a mirror optically coupled with the superconducting film, the mirror arranged to reflect the one or more photons toward the superconducting film;
• wherein said superconducting film has a dimension which allows detection of the one or more photons when said superconducting film is maintained at a temperature below its critical temperature and biased below its critical current;
• and
• wherein the one or more photons may be directly incident upon the superconducting film or reflected off the mirror onto the superconducting film.