Teleportation fidelity of quantum repeater networks

TL;DR

This paper introduces a measure based on teleportation fidelity to evaluate the overall resourcefulness of quantum repeater networks, analyzing fundamental topologies with analytic results and identifying conditions for quantum advantage.

Contribution

It proposes a new network-wide measure based on teleportation fidelity and analytically characterizes simple topologies in various realistic scenarios.

Findings

Analytic expressions for teleportation fidelity in star, chain, and tree topologies.

Identification of parameter regimes for quantum advantage.

Large network size behaviors of the fidelity measure.

Abstract

We show that the average of the maximum teleportation fidelities between all pairs of nodes in a large quantum repeater network is a measure of the resourcefulness of the network as a whole. We use simple Werner state-based models to characterise some fundamental (loopless) topologies (star, chain, and some trees) with respect to this measure in three (semi)realistic scenarios. Most of our results are analytic and are applicable for arbitrary network sizes. We identify the parameter ranges where these networks can achieve quantum advantages and show the large-N behaviours.