Electronics and Communications in Japan (Part II Electronics)
Single‐photon detector for long‐distance quantum cryptography
Naoto Namekata, Yuuki Makino, Shuichiro Inoue
Abstract
Abstract In order to realize long‐distance quantum cryptography based on standard optical fiber network, we have developed a single‐photon detector at 1550 nm using InGaAs/InP avalanche photodiodes (APDs). To reduce the dark count probability, APDs were cooled and operated with a Gated Passive Quenching Circuit. A quantum efficiency of 13.7% was obtained at −55 °C while keeping the dark count probability per gate (2 ns) as low as 2.4 × 10−5. In this paper we will discuss the performance of the developed single‐photon detector in view of application to quantum cryptography. © 2003 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 86(5): 10–15, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/ecjb.10115