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arXiv · 2101.01988

Cavity-Enhanced Atom-Photon Entanglement with Subsecond Lifetime

Xu-Jie Wang·Sheng-Jun Yang·Peng-Fei Sun·Bo Jing·Jun Li·Ming-Ti Zhou·Xiao-Hui Bao·Jian-Wei Pan
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Abstract

A cold atomic ensemble suits well for optical quantum memories, and its entanglement with a single photon forms the building block for quantum networks that give promise for many revolutionary applications. Efficiency and lifetime are among the most important figures of merit for a memory. In this paper, we report the realization of entanglement between an atomic ensemble and a single-photon with subsecond lifetime and high efficiency. We engineer dual control modes in a ring cavity to create entanglement and make use of 3-dimensional optical lattice to prolong memory lifetime. The memory efficiency is 38% for 0.1 second storage. We verify the atom-photon entanglement after 1 second storage by testing the Bell inequality with a result of $S=2.36\pm0.14$.

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quant-phphysics.atom-phphysics.optics

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Xu-Jie Wang, Sheng-Jun Yang, Peng-Fei Sun, Bo Jing, Jun Li, Ming-Ti Zhou, Xiao-Hui Bao, Jian-Wei Pan. 2021-01-06. Cavity-Enhanced Atom-Photon Entanglement with Subsecond Lifetime. https://doi.org/10.1103/physrevlett.126.090501

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