Generating the local oscillator "locally" in continuous-variable quantum key distribution based on coherent detection

Bing Qi, Pavel Lougovski, Raphael Pooser, Warren Grice, Miljko Bobrek

Research output: Contribution to journalArticlepeer-review

266 Scopus citations

Abstract

Continuous-variable quantum key distribution (CV-QKD) protocols based on coherent detection have been studied extensively in both theory and experiment. In all the existing implementations of CV-QKD, both the quantum signal and the local oscillator (LO) are generated from the same laser and propagate through the insecure quantum channel. This arrangement may open security loopholes and limit the potential applications of CV-QKD. In this paper, we propose and demonstrate a pilot-aided feedforward data recovery scheme that enables reliable coherent detection using a "locally" generated LO. Using two independent commercial laser sources and a spool of 25-km optical fiber, we construct a coherent communication system. The variance of the phase noise introduced by the proposed scheme is measured to be 0.04 (rad2), which is small enough to enable secure key distribution. This technology also opens the door for other quantum communication protocols, such as the recently proposed measurement-device-independent CV-QKD, where independent light sources are employed by different users.

Original languageEnglish
Article number041009
JournalPhysical Review X
Volume5
Issue number4
DOIs
StatePublished - 2015

Fingerprint

Dive into the research topics of 'Generating the local oscillator "locally" in continuous-variable quantum key distribution based on coherent detection'. Together they form a unique fingerprint.

Cite this