Quantum Correlations over Long-distances Using Noisy Quantum Repeaters

TL;DR

This paper explores how noisy quantum repeaters can distribute quantum correlations over long distances, revealing their role in enhancing quantum communication and key distillation protocols.

Contribution

It introduces the concept of noisy quantum repeaters and analyzes their impact on quantum correlations and secrecy in quantum communication.

Findings

Noisy quantum repeaters naturally generate private states.

Key distillation protocols become more tolerant with noisy repeaters.

Quantum correlations can be effectively distributed over long distances despite noise.

Abstract

Quantum correlations as the resource for quantum communication can be distributed over long distances by quantum repeaters. In this Letter, we introduce the notion of a noisy quantum repeater, and examine its role in quantum communication. Quantum correlations shared through noisy quantum repeaters are then characterized and their secrecy properties are studied. Remarkably, noisy quantum repeaters naturally introduce private states in the key distillation scenario, and consequently key distillation protocols are demonstrated to be more tolerant.