Efficient long distance quantum communication

TL;DR

This paper systematically compares three generations of quantum repeaters, evaluating their resource costs to identify optimal architectures for efficient long-distance quantum communication, advancing the development of transcontinental quantum networks.

Contribution

It provides the first comprehensive comparison of quantum repeater generations, guiding experimental efforts for efficient long-distance quantum communication.

Findings

Optimal quantum repeater architecture identified for specific parameters

Resource cost analysis for different repeater generations

Roadmap for experimental realization of quantum networks

Abstract

Despite the tremendous progress of quantum cryptography, efficient quantum communication over long distances (>1000km) remains an outstanding challenge due to fiber attenuation and operation errors accumulated over the entire communication distance. Quantum repeaters, as a promising approach, can overcome both photon loss and operation errors, and hence significantly speedup the communication rate. Depending on the methods used to correct loss and operation errors, all the proposed QR schemes can be classified into three categories (generations). Here we present the first systematic comparison of three generations of quantum repeaters by evaluating the cost of both temporal and physical resources, and identify the optimized quantum repeater architecture for a given set of experimental parameters. Our work provides a roadmap for the experimental realizations of highly efficient quantum networks over transcontinental distances.