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arXiv · 0912.2525

Storage and recall of weak coherent optical pulses with an efficiency of 25%

M. Sabooni·F. Beaudoin·A. Walther·N. Lin·A. Amari·M. Huang·S. Kröll
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Abstract

We demonstrate experimentally a quantum memory scheme for the storage of weak coherent light pulses in an inhomogeneously broadened optical transition in a Pr^{3+}: YSO crystal at 2.1 K. Precise optical pumping using a frequency stable (about 1kHz linewidth) laser is employed to create a highly controllable Atomic Frequency Comb (AFC) structure. We report single photon storage and retrieval efficiencies of 25%, based on coherent photon echo type re-emission in the forward direction. The coherence property of the quantum memory is proved through interference between a super Gaussian pulse and the emitted echo. Backward retrieval of the photon echo emission has potential for increasing storage and recall efficiency.

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M. Sabooni, F. Beaudoin, A. Walther, N. Lin, A. Amari, M. Huang, S. Kröll. 2009-12-14. Storage and recall of weak coherent optical pulses with an efficiency of 25%. https://doi.org/10.1103/physrevlett.105.060501

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