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arXiv · 1701.03317

Interfacing a two-photon NOON state with an atomic quantum memory

Wei Zhang·Ming-Xin Dong·Dong-Sheng Ding·Shuai Shi·Kai-Wang·Zhi-Yuan Zhou·Guang-Can Guo·Bao-Sen Shi
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Abstract

Multi-photon entangled states play a crucial role in quantum information applications such as secure quantum communication, scalable computation, and high-precision quantum metrology. Quantum memory for entangled states is a key component of quantum repeaters, which are indispensable in realizing quantum communications. Storing a single photon or an entangled photon has been realized through different protocols. However, there has been no report demonstrating whether a multi-photon state can be stored in any physical system or not. Here, we report on the experimental storage of a two-photon NOON state in a cold atomic ensemble. Quantum interference measured before and after storage clearly shows that the properties of the two-photon NOON state are preserved during storage. Our experiment completes the first step towards storing a multi-photon entangled state.

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Wei Zhang, Ming-Xin Dong, Dong-Sheng Ding, Shuai Shi, Kai-Wang, Zhi-Yuan Zhou, Guang-Can Guo, Bao-Sen Shi. 2017-01-12. Interfacing a two-photon NOON state with an atomic quantum memory. https://doi.org/10.1103/physreva.98.063820

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