Decoy-state round-robin differential-phase-shift quantum key distribution with source errors

TL;DR

This paper analyzes the impact of source errors on the performance of decoy-state round-robin differential-phase-shift quantum key distribution (RRDPS-QKD) and proposes a secure key rate formulation considering these errors.

Contribution

It introduces a three-intensity decoy-state RRDPS-QKD protocol that accounts for source errors, providing a new method to evaluate secure key rates under practical conditions.

Findings

Source errors significantly affect RRDPS-QKD performance.

The proposed model accurately estimates the influence of source errors.

Numerical simulations validate the effectiveness of the evaluation method.

Abstract

As a promising quantum key distribution (QKD), most of the existing round-robin differential-phase-shift quantum key distribution (RRDPS-QKD) protocols have adopted the decoy-state method and have assumed the source states are exactly controlled. However, the precise manipulation of source states is impossible for any practical experiment, and the RRDPS-QKD with source errors has an unignorable impact on the performance of the protocol. In the paper, we study the three-intensity decoy-state RRDPS-QKD protocol with source errors, formulate the secure generation key rate of the proposed protocol, do the numerical simulations to testify the deductions. The results show that our evaluation can estimate the influence of source errors.