Tight finite-key analysis for quantum cryptography

By Marco Tomamichel, Charles Ci Wen Lim, Nicolas Gisin, Renato Renner. Nature Communications, 2011

633 citations recorded by the source corpus.

Despite enormous theoretical and experimental progress in quantum cryptography, the security of most current implementations of quantum key distribution is still not rigorously established. One significant problem is that the security of the final key strongly depends on the number, M, of signals exchanged between the legitimate parties. Yet, existing security proofs are often only valid asymptotically, for unrealistically large values of M. Another challenge is that most security proofs are very sensitive to small differences between the physical devices used by the protocol and the theoretical model used to describe them. Here we show that these gaps between theory and experiment can be simultaneously overcome by using a recently developed proof technique based on the uncertainty relation for smooth entropies. Although they offer significant promise, practical implementations of quantum key distribution are often not as rigorous as theory predicts. This study demonstrates how two instances of such discrepancies can be resolved by taking advantage of an enotropic formulation of the uncertainty principle.

Subfields: Artificial Intelligence, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/4b95690ba97bc47d0e36716007401e485337ba93

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Citations in the corpus

Advances in quantum cryptography (2019, neutral): “Therefore, it only remains to statistically estimate H max(Y n|Ŷ ), which can be done by calculating the number of bit discrepancies between Alice and Bob on a random sample of the raw keys [496].”
Quantum Information Processing with Finite Resources - Mathematical Foundations (2015, background): “of continuous observables (e.g. position and momentum) 7.4 Background and Further Reading 115 by Furrer et al. [61]. These entropic URs lie at the core of security proofs for quantum key distribution [62,158]. There exist other protocol families that extract the min-entropy against quantum adversari”
Secure quantum key distribution with realistic devices (2020, methodology): “This approach has been applied to QKD to prove the finite-key security with almost tight bounds (Tomamichel et al., 2012; Tomamichel and Renner, 2011).”
A link layer protocol for quantum networks (2019, background): “Precise statistical statements are relatively straightforward but very lengthy - to obtain using the techniques in [79, 95] and are out of scope of this paper.”
Fundamental rate-loss tradeoff for optical quantum key distribution (2014, background): “Since the function in (6) is symmetric and convex in Z1, its minimum”