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arXiv · 2503.18906

Entanglement swapping systems toward a quantum internet

Samantha I. Davis·Raju Valivarthi·Andrew Cameron·Cristian Pena·Si Xie·Lautaro Narvaez·Nikolai Lauk·Chang Li·Kelsie Taylor·Rahaf Youssef·Christina Wang·Keshav Kapoor·Boris Korzh·Neil Sinclair·Matthew Shaw·Panagiotis Spentzouris·Maria Spiropulu
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Abstract

We demonstrate conditional entanglement swapping, i.e. teleportation of entanglement, between time-bin qubits at the telecommunication wavelength of 1536.4 nm with high fidelity of 87\%. Our system is deployable, utilizing modular, off-the-shelf, fiber-coupled, and electrically controlled components such as electro-optic modulators. It leverages the precise timing resolution of superconducting nanowire detectors, which are controlled and read out via a custom developed graphical user interface. The swapping process is described, interpreted, and guided using characteristic function-based analytical modeling that accounts for realistic imperfections. Our system supports quantum networking protocols, including source-independent quantum key distribution, with an estimated secret key rate of approximately 0.5 bits per sifted bit.

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Samantha I. Davis, Raju Valivarthi, Andrew Cameron, Cristian Pena, Si Xie, Lautaro Narvaez, Nikolai Lauk, Chang Li, Kelsie Taylor, Rahaf Youssef, Christina Wang, Keshav Kapoor, Boris Korzh, Neil Sinclair, Matthew Shaw, Panagiotis Spentzouris, Maria Spiropulu. 2025-03-24. Entanglement swapping systems toward a quantum internet. https://arxiv.org/abs/2503.18906

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