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Conference on Lasers and Electro-Optics

Highly-efficient entanglement storage of light in cold-atom quantum memories

Félix Hoffet, Mingtao Cao, Shuwei Qiu, A. S. Sheremet, Hadriel Mamann, Thomas Nieddu, Julien Laurat

Published Jan 1, 2021• 1 citation
Publisher

Abstract

Highly-efficient entanglement storage in quantum memories is a critical requirement for quantum networks. We present an experiment where we stored single-photon entanglement into two atomic-ensemble based quantum memories with an overall efficiency of 87%.
DOI
10.1364/cleo_qels.2021.fm4m.7

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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 Letter, 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 three-dimensional optical lattice to prolong memory lifetime. The memory efficiency is 38% for 0.1 s storage. We verify the atom-photon entanglement after 1 s storage by testing the Bell inequality with a result of S=2.36±0.14.
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