IEEE International Conference on Space Optical Systems and Applications (ICSOS)

Development of practical superconducting nanowire single photon detector system with high detection efficiency

Shigehito Miki, Taro Yamashita, Hirotaka Terai, Mikio Fujiwara, Masahide Sasaki, Zhen Wang

Published May 1, 2011• 0 citations

Abstract

We have developed a practical superconducting nanowire single photon detector (SNSPD) system with our superconducting thin films and devices fabrication, optical coupling packaging, and cryogenic technology. The SNSPD devices were fabricated from high-quality niobium nitride (NbN) ultra-thin films that were epitaxially grown on single-crystal MgO substrates, and optical cavity structure were applied for improvement of photo absorption efficiency. The SNSPD system was developed based on a compact Gifford-McMahon (GM) cryocooler, in which SNSPD can operate continuously at temperature of 2.9 K +/- 10 mK with low power consumption without any liquid cryogens. The system detection efficiencies at 1550 nm wavelength (at a 100 Hz dark count rate) were found to be 2.6% for device without optical cavity and 21% for device with optical cavity. The response speed of devices showed maximally 200 MHz with 5 × 5 mm square device, and timing jitter of 100 ps full width at a half maximum (FWHM) was observed.

DOI: 10.1109/icsos.2011.5783658

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