Quantum key distribution using deterministic single-photon sources over a field-installed fibre link

Autor: Mujtaba Zahidy, Mikkel T. Mikkelsen, Ronny Müller, Beatrice Da Lio, Martin Krehbiel, Ying Wang, Nikolai Bart, Andreas D. Wieck, Arne Ludwig, Michael Galili, Søren Forchhammer, Peter Lodahl, Leif K. Oxenløwe, Davide Bacco, Leonardo Midolo
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: npj Quantum Information, Vol 10, Iss 1, Pp 1-6 (2024)
Druh dokumentu: article
ISSN: 2056-6387
DOI: 10.1038/s41534-023-00800-x
Popis: Abstract Quantum-dot-based single-photon sources are key assets for quantum information technology, supplying on-demand scalable quantum resources for computing and communication. However, long-lasting issues such as limited long-term stability and source brightness have traditionally impeded their adoption in real-world applications. Here, we realize a quantum key distribution field trial using true single photons across an 18-km-long dark fibre, located in the Copenhagen metropolitan area, using an optimized, state-of-the-art, quantum-dot single-photon source frequency-converted to the telecom wavelength. A secret key generation rate of > 2 kbits/s realized over a 9.6 dB channel loss is achieved with a polarization-encoded BB84 scheme, showing remarkable stability for more than 24 hours of continuous operation. Our results highlight the maturity of deterministic single-photon source technology while paving the way for advanced single-photon-based communication protocols, including fully device-independent quantum key distribution, towards the goal of a quantum internet.
Databáze: Directory of Open Access Journals