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arXiv · 1601.00157

Theory of noise suppression in {\Lambda}-type quantum memories by means of a cavity

J. Nunn·S. Thomas·J. H. D. Munns·K. T. Kaczmarek·C. Qiu·A. Feizpour·E. Poem·B. Brecht·D. J. Saunders·P. M. Ledingham·Dileep V. Reddy·M. G. Raymer·I. A. Walmsley
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Abstract

Quantum memories, capable of storing single photons or other quantum states of light, to be retrieved on-demand, offer a route to large-scale quantum information processing with light. A promising class of memories is based on far-off-resonant Raman absorption in ensembles of $\Lambda$-type atoms. However at room temperature these systems exhibit unwanted four-wave mixing, which is prohibitive for applications at the single-photon level. Here we show how this noise can be suppressed by placing the storage medium inside a moderate-finesse optical cavity, thereby removing the main roadblock hindering this approach to quantum memory.

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J. Nunn, S. Thomas, J. H. D. Munns, K. T. Kaczmarek, C. Qiu, A. Feizpour, E. Poem, B. Brecht, D. J. Saunders, P. M. Ledingham, Dileep V. Reddy, M. G. Raymer, I. A. Walmsley. 2016-01-02. Theory of noise suppression in {\Lambda}-type quantum memories by means of a cavity. https://doi.org/10.1103/physreva.96.012338

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