qkdSim: An experimenter's simulation toolkit for QKD with imperfections, and its performance analysis with a demonstration of the B92 protocol using heralded photon

TL;DR

This paper introduces qkdSim, a simulation toolkit for quantum key distribution that models experimental imperfections, demonstrated with the B92 protocol showing close agreement between simulated and experimental results.

Contribution

The work presents the design and implementation of qkdSim, a versatile simulation software for QKD protocols incorporating real-world imperfections, validated through experimental demonstration of B92.

Findings

Simulation closely matches experimental key rate and QBER.

qkdSim accurately models experimental imperfections in QKD.

Demonstrated the B92 protocol with realistic simulation results.

Abstract

Quantum Key Distribution (QKD) is one of the most important aspects of quantum cryptography. Using laws of quantum mechanics as the basis for security, the key distribution process is made information theoretically secure in QKD. With the advancement and commercialization of QKD, an end-to-end QKD simulation software is required that can include experimental imperfections. Software of this kind will ensure that resources are invested only after prior performance analysis, and is faithful to experimental capacities and limitations. In this work, we introduce our QKD simulation toolkit qkdSim, which is ultimately aimed at being developed into such a software package that can precisely model and analyse any generic QKD protocol. We present the design, implementation and testing of a prototype of qkdSim that can accurately simulate our own experimental demonstration of the B92 protocol. The simulation results match well with experiment; a representative key rate and QBER from experiment is $51 \pm 0.5$ Kbits/sec and $4.79\% \pm 0.01\%$ respectively, wherein the simulation yields $52.83 \pm 0.36$ Kbits/sec and $4.79\% \pm 0.01\%$ respectively.