Statistical fluctuation analysis for measurement-device-independent quantum key distribution

TL;DR

This paper analyzes finite-data-size effects in measurement-device-independent quantum key distribution with decoy states, demonstrating conditions under which practical, secure, and efficient implementations are feasible.

Contribution

It introduces a statistical fluctuation analysis for finite data in MDI-QKD with decoy states, identifying operational regimes close to ideal asymptotic performance.

Findings

Finite-data analysis shows practical regimes with near-asymptotic performance.

Vacuum+weak- and vacuum+two-weak-decoy protocols are effective under finite data.

Results support secure and efficient real-world MDI-QKD implementations.

Abstract

Measurement-device-independent quantum key distribution with a finite number of decoy states is analyzed under finite-data-size assumption. By accounting for statistical fluctuations in parameter estimation, we investigate vacuum+weak- and vacuum+two-weak-decoy-state protocols. In each case, we find proper operation regimes, where the performance of our system is comparable to the asymptotic case for which the key size and the number of decoy states approach infinity. Our results show that practical implementations of this scheme can be both secure and efficient.