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arXiv · 2401.10697

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

Jingyuan Liu·Dongning Liu·Zhanping Jin·Zhihao Lin·Hao Li·Lixing You·Xue Feng·Fang Liu·Kaiyu Cui·Yidong Huang·Wei Zhang
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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.

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Jingyuan Liu, Dongning Liu, Zhanping Jin, Zhihao Lin, Hao Li, Lixing You, Xue Feng, Fang Liu, Kaiyu Cui, Yidong Huang, Wei Zhang. 2024-01-19. Reconfigurable entanglement distribution network based on pump management of spontaneous four-wave mixing source. https://arxiv.org/abs/2401.10697

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