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arXiv · 2411.15437

Faithful quantum teleportation via a nanophotonic nonlinear Bell state analyzer

Joshua Akin·Yunlei Zhao·Paul G. Kwiat·Elizabeth A. Goldschmidt·Kejie Fang
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Abstract

Quantum networking protocols, including quantum teleportation and entanglement swapping, use linear-optical Bell state measurements for heralding the distribution and transfer of quantum information. However, a linear-optical Bell state measurement requires identical photons and is susceptible to errors caused by multiphoton emission, fundamentally limiting the efficiency and fidelity of quantum networking protocols. Here we show a nonlinear Bell state analyzer for time-bin encoded photons based on a nanophotonic cavity with efficient sum-frequency generation to filter multiphoton emissions, and utilize it for faithful quantum teleportation involving spectrally distinct photons with fidelities $\geq 94\%$ down to the single-photon level. Our result demonstrates that nonlinear-optical entangling operations, empowered by our efficient nanophotonics platform, can realize faithful quantum information protocols without requiring identical photons and without the fundamental limit on the efficiency and fidelity of a Bell state measurement imposed by linear optics, which facilitates the realization of practical quantum networks.

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Joshua Akin, Yunlei Zhao, Paul G. Kwiat, Elizabeth A. Goldschmidt, Kejie Fang. 2024-11-23. Faithful quantum teleportation via a nanophotonic nonlinear Bell state analyzer. https://doi.org/10.1103/physrevlett.134.160802

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