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arXiv · 2401.04327

Implementation of space-division multiplexed entanglement-based quantum cryptography over multicore fiber

Evelyn A. Ortega·Jorge Fuenzalida·Krishna Dovzhik·Rodrigo F. Shiozaki·Juan Carlos Alvarado-Zacarias·Rodrigo Amezcua-Correa·Martin Bohmann·Sören Wengerowsky·Rupert Ursin
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Abstract

Quantum communication implementations require efficient and reliable quantum channels. Optical fibers have proven to be an ideal candidate for distributing quantum states. Thus, today's efforts address overcoming issues towards high data transmission and long-distance implementations. Here, we experimentally demonstrate the secret key rate enhancement via space-division multiplexing using a multicore fiber. Our multiplexing technique exploits the momentum correlation of photon pairs generated by spontaneous parametric down-conversion. We distributed polarization-entangled photon pairs into opposite cores within a 19-core multicore fiber. We estimated the secret key rates in a configuration with 6 and 12 cores from the entanglement visibility after transmission through 411 m long multicore fiber.

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Evelyn A. Ortega, Jorge Fuenzalida, Krishna Dovzhik, Rodrigo F. Shiozaki, Juan Carlos Alvarado-Zacarias, Rodrigo Amezcua-Correa, Martin Bohmann, Sören Wengerowsky, Rupert Ursin. 2024-01-09. Implementation of space-division multiplexed entanglement-based quantum cryptography over multicore fiber. https://doi.org/10.1364/opticaq.527903

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