Quantum key distribution with a bright telecom wavelength quantum dot single-photon source

Abstract

A source of bright and pure single photons is an essential tool for photonic quantum technologies, predicted to enable secure communication and networking. Self-assembled quantum dots are among the leading candidates to realise such a source. The currently highest-performing quantum dots emit at wavelengths unsuitable for fibre transmission, with telecom quantum dots lagging in performance. An intermediate step is to use quantum frequency conversion. Here we report to our knowledge the brightest quantum dot based source of telecom photons by frequency converting a near-infrared quantum dot embedded in a micropillar cavity to the telecom C-band. In a single-photon BB84 protocol, this source is capable of producing asymptotic keys rates of 1 kbps at over 150 km of optical fibre.

Authors 7

1. Christopher L. Morrison

   Heriot-Watt University

   Affiliation as printed

   Heriot-Watt Univ. (United Kingdom)

2. Francesco Graffitti

   Heriot-Watt University

   Affiliation as printed

   Heriot-Watt Univ. (United Kingdom)

3. Zhe Xian Koong

   Heriot-Watt University

   Affiliation as printed

   Heriot-Watt Univ. (United Kingdom)

4. Nick Stoltz

   University of California, Santa Barbara

   Affiliation as printed

   Univ. of California, Santa Barbara (United States)

5. Dirk Bouwmeester Aachen Leiden Univ. (Netherlands)

   Leiden University

   Affiliation as printed

   Leiden Univ. (Netherlands)

6. Alessandro Fedrizzi

   Heriot-Watt University

   Affiliation as printed

   Heriot-Watt Univ. (United Kingdom)

7. Brian D. Gerardot

   Heriot-Watt University

   Affiliation as printed

   Heriot-Watt Univ. (United Kingdom)