NIST physicists have developed single photon detectors with a record 88% efficiency, a significant advancement for practical quantum cryptography systems. The detectors, made of a thin tungsten film, operate at near-infrared wavelengths used in fiber-optic communications. By depositing the tungsten over a metallic mirror and adding an anti-reflective coating, NIST scientists more than quadrupled the detection efficiency compared to previous designs.
The new detectors could be used as receivers for quantum communications systems, calibration tools for single photon sources, and evaluation tools for testing system security. Simulations suggest it may be possible to achieve over 99% efficiency by optimizing the optical structure. This breakthrough could enable more reliable and secure quantum cryptography systems, as well as advance research in quantum physics and ultralow light optical systems.
Source: https://www.nist.gov/news-events/news/2005/06/nist-photon-detectors-have-record-efficiency
Keywords: photon, detector, efficiency, quantum, cryptography
