arXiv:1404.3489 · New Journal of Physics

Cavity-enhanced storage in an optical spin-wave memory

Pierre Jobez, Imam Usmani, Nuala Timoney, Cyril Laplane, Nicolas Gisin, Mikael Afzelius

Published Aug 4, 2014• 144 citations

Abstract

We report on the experimental demonstration of an optical spin-wave memory, based on the atomic frequency comb (AFC) scheme, where the storage efficiency is strongly enhanced by an optical cavity. The cavity is of low finesse, but operated in an impedance matching regime to achieve high absorption in our intrinsically low-absorbing Eu 3+ :Y 2 SiO 5 crystal. For storage of optical pulses as an optical excitation (AFC echoes), we reach efficiencies of 53% and 28% for 2 μ s and 10 μ s delays, respectively. For a complete AFC spin-wave memory we reach an efficiency of 12%, including spin-wave dephasing, which is a 12-fold increase with respect to previous results in this material. This result is an important step towards the goal of making efficient and long-lived quantum memories based on spin waves, in the context of quantum repeaters and quantum networks.

DOI: 10.1088/1367-2630/16/8/083005

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