Reconfigurable entanglement distribution network based on pump management of spontaneous four-wave mixing source

TL;DR

This paper introduces a reconfigurable quantum entanglement distribution network utilizing tunable multi-pump SFWM sources and time-sharing, enabling scalable, flexible, and large-scale quantum key distribution among multiple users.

Contribution

It presents a novel reconfigurable entanglement network based on tunable multi-pump SFWM and demonstrates its scalability and reconfigurability through a 10-user QKD setup.

Findings

Two-photon correlation is tunable via pump conditions.

A 10-user fully-connected QKD network is demonstrated.

Linear scaling between user number and frequency channels.

Abstract

Leveraging the unique properties of quantum entanglement, quantum entanglement distribution networks support multiple quantum information applications and are essential to the development of quantum networks. However, its practical implementation poses significant challenges to network scalability and flexibility. In this work, we propose a novel reconfigurable entanglement distribution network based on tunable multi-pump excitation of a spontaneous four-wave mixing (SFWM) source and a time-sharing method. We characterize the two-photon correlation under different pump conditions to demonstrate the effect of pump degenerate and pump non-degenerate SFWM processes on the two-photon correlation, and its tunability. Then as a benchmark application, a 10-user fully-connected quantum key distribution (QKD) network is established in a time-sharing way with triple pump lights. Each user receives one frequency channel thus it shows a linear scaling between the number of frequency channels and the user number in despite of the network topology. Our results thus provide a promising networking scheme for large-scale entanglement distribution networks owing to its scalability, functionality, and reconfigurability.