Sending-or-not twin-field quantum key distribution in practice

TL;DR

This paper demonstrates a practical implementation of sending-or-not twin-field quantum key distribution, addressing real-world constraints like limited intensities, phase slice size, and statistical fluctuations, ensuring security and efficiency.

Contribution

It introduces a decoy-state method with limited intensities and phase slices, along with a statistical fluctuation analysis, making practical QKD more feasible.

Findings

Performance comparable to asymptotic case with large key size

Practical method maintains security and efficiency

Decoy-state method effective with limited parameters

Abstract

We present results of practical sending-or-not quantum key distribution. In real-life implementations, we need consider the following three requirements, a few different intensities rather than infinite number of different intensities, a phase slice of appropriate size rather than infinitely small size and the statistical fluctuations. We first show the decoy-state method with only a few different intensities and a phase slice of appropriate size. We then give a statistical fluctuation analysis for the decoy-state method. Numerical simulation shows that, the performance of our method is comparable to the asymptotic case for which the key size is large enough. Our results show that practical implementations of the sending-or-not quantum key distribution can be both secure and efficient.