High-efficiency Coherent Optical Memory based on Electromagnetically Induced Transparency.

POSTER

Abstract

Quantum memory is a crucial component in the long-distance quantum communication based on quantum repeaters. To outperform the direct transmission of photons with quantum repeaters, it is crucial to develop quantum memories with high fidelity, high efficiency and a long storage time. Here, we present our work to achieve a storage efficiency of larger than 90{\%} for a coherent memory based on the electromagnetically induced transparency (EIT) scheme in cold atomic media with an optical depth of \textasciitilde 1000. At a storage efficiency of 50{\%}, we also obtain a fractional delay of 1200. At high optical depths, nonlinear optical effects, such as the photon switching and four-wave mixing due to the off-resonant excitation of the EIT control field, may become significant and introduce complications in quantum memory applications. We discuss and present methods to reduce these complications.

Authors

  • Ying-Cheng Chen

    • Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
    • Inst. of Atomic and Molecular Sci., Academia Sinica, Taiwan

  • Ya-Fen Hsiao

    • Molecular Science and Technology, Taiwan International Graduate Program, Academia Sinica and National Central University, Taiwan

  • Pin-Ju Tsai

    • Department of Physics, National Taiwan University, Taiwan

  • Hung-Shiue Chen

    • Institute of Atomic and Molecular Sciences, Academia Sinica, Taiwan

  • Sheng-Xiang Lin

    • Department of Physics, National Taiwan University, Taiwan

  • Chih-Chiao Hung

    • Department of Physics, National Taiwan University, Taiwan

  • Chih-Hsi Lee

    • Department of Physics, National Taiwan University, Taiwan

  • Yi-Hsin Chend

    • Department of Physics, National Tsing Hua University, Taiwan

  • Yong-Fan Chen

    • Department of Physics, National Cheng Kung University, Taiwan

  • Ite Albert Yu

    • Department of Physics, National Tsing Hua University, Taiwan