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arXiv · 2011.14948

Efficient quantum memory for heralded single photons generated by cavity-enhanced spontaneous parametric downconversion

Yu-Chih Tseng·Yan-Cheng Wei·Ying-Cheng Chen
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Abstract

We interface a spontaneous parametric down conversion (SPDC) crystal and a cold atomic ensemble and demonstrate a highly efficient quantum memory through polarization-encoded single-photon qubits. Specifically, narrowband heralded single photons from a cavity-enhanced SPDC source is stored using cold atomic ensemble, with ~70% storage-and-retrieval efficiency and ~10$\mu$s storage time at 50% efficiency. To prevent the degradation after storage, we also manipulate the single-photon wave profile so that the retrieved non-classical nature of single photon is preserved. On the other hand, the dual-rail storage is used for storing polarization-encoded qubits, and the corrected fidelity of flying qubits after storage reaches ~97%. The results pave the way toward large-scale quantum network.

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Yu-Chih Tseng, Yan-Cheng Wei, Ying-Cheng Chen. 2020-11-30. Efficient quantum memory for heralded single photons generated by cavity-enhanced spontaneous parametric downconversion. https://arxiv.org/abs/2011.14948

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