title: A gallium nitride single-photon source operating at 200 K.
abstract: Fundamentally secure quantum cryptography has still not seen widespread application owing to the difficulty of generating single photons on demand. Semiconductor quantum-dot structures have recently shown great promise as practical single-photon sources, and devices with integrated optical cavities and electrical-carrier injection have already been demonstrated. However, a significant obstacle for the application of commonly used III-V quantum dots to quantum-information-processing schemes is the requirement of liquid-helium cryogenic temperatures. Epitaxially grown gallium nitride quantum dots embedded in aluminium nitride have the potential for operation at much higher temperatures. Here, we report triggered single-photon emission from gallium nitride quantum dots at temperatures up to 200 K, a temperature easily reachable with thermo-electric cooling. Gallium nitride quantum dots also open a new wavelength region in the blue and near-ultraviolet portions of the spectrum for single-photon sources.
authors.affiliation: Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Tokyo 153-8505, Japan. kako@iis.u-tokyo.ac.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kako
authors.forename: Charles
authors.initials: C
authors.lastname: Santori
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Hoshino
authors.forename: Stephan
authors.initials: S
authors.lastname: Götzinger
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Arakawa