A new superconducting device detects single light quanta, photons, at wavelengths longer than previously possible, and does so with remarkable speed and sensitivity. The superconducting material, niobium nitride, is capable of detecting individual photons at a rate of 25 billion per second. The device detects light in a portion of the infrared spectrum -- from 3 to 10 micrometers -- that is transmitted by the atmosphere making it important for telecommunications and infrared astronomy. The device's speed combined with its small size and its ability to detect changes in light level also makes it a candidate for the input component of a superconducting computer. A University of Rochester scientist and his Russian colleagues from Moscow State Pedagogical University developed the superconducting device as part of an ONR-funded effort to promote international cooperation among scientist in the post-Cold War era. The films were made and tested in Moscow. The device's speed was measured at the University of Rochester. These research results were published in the December 28 issue of Applied Physics Letters.