From quantum fusiliers to high-performance networks

TL;DR

This paper discusses advancements in quantum repeater design aiming for high entanglement generation rates over long distances, approaching one million pairs per second, through novel entanglement creation mechanisms.

Contribution

It introduces a near-perfect, constant-time entanglement mechanism and demonstrates its application in constructing high-fidelity, high-rate quantum repeaters for long-distance networks.

Findings

Entanglement creation probability can be made arbitrarily close to one.

Mechanism operates in constant time regardless of distance.

Quantum repeater design achieves high fidelity over 1000 km.

Abstract

Our objective was to design a quantum repeater capable of achieving one million entangled pairs per second over a distance of 1000km. We failed, but not by much. In this letter we will describe the series of developments that permitted us to approach our goal. We will describe a mechanism that permits the creation of entanglement between two qubits, connected by fibre, with probability arbitrarily close to one and in constant time. This mechanism may be extended to ensure that the entanglement has high fidelity without compromising these properties. Finally, we describe how this may be used to construct a quantum repeater that is capable of creating a linear quantum network connecting two distant qubits with high fidelity. The creation rate is shown to be a function of the maximum distance between two adjacent quantum repeaters.