Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Research Highlight
  • Published:

QUANTUM OPTICS

Twin-field QKD

Nature Photonics volume 12, page 377 (2018)Cite this article

Subjects

Access through your institution
Buy or subscribe

Nature 557, 400–403 (2018)

Quantum repeaters are likely to be needed in order to overcome existing bounds of quantum communications, but making practical devices remains challenging. For example, in quantum key distribution (QKD), there are fundamental rate–distance limits (related to the maximum secret key rate that is possible for a given transmission distance) and without quantum repeaters this issue remains a hurdle. Marco Lucamarini and a team at Toshiba Research Europe (Cambridge, UK) have now proposed a twin-field QKD approach that, without quantum repeaters, may enable 550 km QKD with acceptable noise using standard optical fibre; this would go beyond the typical ~200–340 km repeaterless bounds of QKD with standard optical fibre. Two light sources are required in twin-field QKD, creating the pulses for each user (‘Alice’ and ‘Bob’) that are phase-randomized and phase-encoded with secret bits. On interference of the pulses at a beam splitter, an eavesdropper ‘Charlie’ is able to infer whether the secrets bits of Alice and Bob are the same or different (that is, 00 or 11 versus 01 or 10), but is unable to determine the absolute values (0 or 1), making the scheme resistant to hacking.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Access through your institution

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Author information

Authors and Affiliations

  1. Nature Photonics https://www.nature.com/naturephotonics

    David F. P. Pile

Authors
  1. David F. P. Pile
    View author publications

    Search author on:PubMed Google Scholar

Corresponding author

Correspondence to David F. P. Pile.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Pile, D.F.P. Twin-field QKD. Nature Photon 12, 377 (2018). https://doi.org/10.1038/s41566-018-0209-1

Download citation

  • Published:

  • Issue date:

  • DOI: https://doi.org/10.1038/s41566-018-0209-1

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing