Provably secure and high-rate quantum key distribution with time-bin qudits.

Published

Journal Article

The security of conventional cryptography systems is threatened in the forthcoming era of quantum computers. Quantum key distribution (QKD) features fundamentally proven security and offers a promising option for quantum-proof cryptography solution. Although prototype QKD systems over optical fiber have been demonstrated over the years, the key generation rates remain several orders of magnitude lower than current classical communication systems. In an effort toward a commercially viable QKD system with improved key generation rates, we developed a discrete-variable QKD system based on time-bin quantum photonic states that can generate provably secure cryptographic keys at megabit-per-second rates over metropolitan distances. We use high-dimensional quantum states that transmit more than one secret bit per received photon, alleviating detector saturation effects in the superconducting nanowire single-photon detectors used in our system that feature very high detection efficiency (of more than 70%) and low timing jitter (of less than 40 ps). Our system is constructed using commercial off-the-shelf components, and the adopted protocol can be readily extended to free-space quantum channels. The security analysis adopted to distill the keys ensures that the demonstrated protocol is robust against coherent attacks, finite-size effects, and a broad class of experimental imperfections identified in our system.

Full Text

Duke Authors

Cited Authors

  • Islam, NT; Lim, CCW; Cahall, C; Kim, J; Gauthier, DJ

Published Date

  • November 24, 2017

Published In

Volume / Issue

  • 3 / 11

Start / End Page

  • e1701491 -

PubMed ID

  • 29202028

Pubmed Central ID

  • 29202028

Electronic International Standard Serial Number (EISSN)

  • 2375-2548

International Standard Serial Number (ISSN)

  • 2375-2548

Digital Object Identifier (DOI)

  • 10.1126/sciadv.1701491

Language

  • eng