Woodward, Robert Ian, Lo, Y. S., Pittaluga, M. et al. (4 more authors) (2021) Gigahertz measurement-device-independent quantum key distribution using directly modulated lasers. npj Quantum Information. ISSN 2056-6387
Abstract
Measurement-device-independent quantum key distribution (MDI-QKD) is a technique for quantum-secured communication that eliminates all detector side-channels, although is currently limited by implementation complexity and low secure key rates. Here, we introduce a simple and compact MDI-QKD system design at gigahertz clock rates with enhanced resilience to laser fluctuations—thus enabling free-running semiconductor laser sources to be employed without spectral or phase feedback. This is achieved using direct laser modulation, carefully exploiting gain-switching and injection-locking laser dynamics to encode phase-modulated time-bin bits. Our design enables secure key rates that improve upon the state of the art by an order of magnitude, up to 8 bps at 54 dB channel loss and 2 kbps in the finite-size regime for 30 dB channel loss. This greatly simplified MDI-QKD system design and proof-of-principle demonstration shows that MDI-QKD is a practical, high-performance solution for future quantum communication networks.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s) 2021 |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Physics (York) |
Funding Information: | Funder Grant number EPSRC UNSPECIFIED |
Depositing User: | Pure (York) |
Date Deposited: | 14 Apr 2021 09:50 |
Last Modified: | 21 Jan 2025 17:53 |
Published Version: | https://doi.org/10.1038/s41534-021-00394-2 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1038/s41534-021-00394-2 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:173070 |
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Filename: mdi_manuscript_npj.pdf
Description: mdi_manuscript_npj
Filename: s41534_021_00394_2.pdf
Description: Gigahertz measurement-device-independent quantum key distribution using directly modulated lasers
Licence: CC-BY 2.5