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arXiv · 2107.09857

Elimination of Noise in Optically Rephased Photon Echoes

You-Zhi Ma·Ming Jin·Duo-Lun Chen·Zong-Quan Zhou·Chuan-Feng Li·Guang-Can Guo
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Abstract

Photon echo is a fundamental tool for the manipulation of electromagnetic fields. Unavoidable spontaneous emission noise is generated in this process due to the strong rephasing pulse, which limits the achievable signal-to-noise ratio and represents a fundamental obstacle towards their applications in the quantum regime. Here we propose a noiseless photon-echo protocol based on a four-level atomic system. We implement this protocol in a Eu3+:Y2SiO5bcrystal to serve as an optical quantum memory. A storage fidelity of 0.952 is obtained for time-bin qubits encoded with single-photon-level coherent pulses, which is far beyond the maximal fidelity achievable using the classical measure-and-prepare strategy. In this work, the demonstrated noiseless photon-echo quantum memory features spin-wave storage, easy operation and high storage fidelity, which should be easily extended to other physical systems.

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You-Zhi Ma, Ming Jin, Duo-Lun Chen, Zong-Quan Zhou, Chuan-Feng Li, Guang-Can Guo. 2021-07-21. Elimination of Noise in Optically Rephased Photon Echoes. https://doi.org/10.1038/s41467-021-24679-4

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