Device-independent quantum key distribution with random key basis

authored by: René Schwonnek, Koon Tong Goh, Ignatius W. Primaatmaja, Ernest Y.Z. Tan, Ramona Wolf, Valerio Scarani, Charles C.W. Lim
Abstract: Device-independent quantum key distribution (DIQKD) is the art of using untrusted devices to distribute secret keys in an insecure network. It thus represents the ultimate form of cryptography, offering not only information-theoretic security against channel attacks, but also against attacks exploiting implementation loopholes. In recent years, much progress has been made towards realising the first DIQKD experiments, but current proposals are just out of reach of today’s loophole-free Bell experiments. Here, we significantly narrow the gap between the theory and practice of DIQKD with a simple variant of the original protocol based on the celebrated Clauser-Horne-Shimony-Holt (CHSH) Bell inequality. By using two randomly chosen key generating bases instead of one, we show that our protocol significantly improves over the original DIQKD protocol, enabling positive keys in the high noise regime for the first time. We also compute the finite-key security of the protocol for general attacks, showing that approximately 10⁸–10¹⁰ measurement rounds are needed to achieve positive rates using state-of-the-art experimental parameters. Our proposed DIQKD protocol thus represents a highly promising path towards the first realisation of DIQKD in practice.
Organisation(s): QuantumFrontiers
External Organisation(s): National University of Singapore
ETH Zurich
Type: Article
Journal: Nature Communications
Volume: 12
ISSN: 2041-1723
Publication date: 01.12.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Chemistry(all), Biochemistry, Genetics and Molecular Biology(all), Physics and Astronomy(all)
Electronic version(s): https://doi.org/10.1038/s41467-021-23147-3 (Access: Open)

BibTeX

@article{8e2c8057ea4b457e9291bca34813c854,
title = "Device-independent quantum key distribution with random key basis",
abstract = "Device-independent quantum key distribution (DIQKD) is the art of using untrusted devices to distribute secret keys in an insecure network. It thus represents the ultimate form of cryptography, offering not only information-theoretic security against channel attacks, but also against attacks exploiting implementation loopholes. In recent years, much progress has been made towards realising the first DIQKD experiments, but current proposals are just out of reach of today{\textquoteright}s loophole-free Bell experiments. Here, we significantly narrow the gap between the theory and practice of DIQKD with a simple variant of the original protocol based on the celebrated Clauser-Horne-Shimony-Holt (CHSH) Bell inequality. By using two randomly chosen key generating bases instead of one, we show that our protocol significantly improves over the original DIQKD protocol, enabling positive keys in the high noise regime for the first time. We also compute the finite-key security of the protocol for general attacks, showing that approximately 108–1010 measurement rounds are needed to achieve positive rates using state-of-the-art experimental parameters. Our proposed DIQKD protocol thus represents a highly promising path towards the first realisation of DIQKD in practice.",
author = "Ren{\'e} Schwonnek and Goh, {Koon Tong} and Primaatmaja, {Ignatius W.} and Tan, {Ernest Y.Z.} and Ramona Wolf and Valerio Scarani and Lim, {Charles C.W.}",
note = "Publisher Copyright: {\textcopyright} 2021, The Author(s).",
year = "2021",
month = dec,
day = "1",
doi = "10.1038/s41467-021-23147-3",
language = "English",
volume = "12",
journal = "Nature Communications",
issn = "2041-1723",
publisher = "Nature Publishing Group",
number = "1",
}