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arXiv · 1704.06309

A Broadband DLCZ Quantum Memory in Room-Temperature Atoms

Jian-Peng Dou·Ai-Lin Yang·Mu-Yan Du·Di Lao·Jun Gao·Lu-Feng Qiao·Hang Li·Xiao-Ling Pang·Zhen Feng·Hao Tang·Xian-Min Jin
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Abstract

Quantum memory capable of stopping flying photons and storing their quantum coherence is essential for scalable quantum technologies. A room-temperature broadband quantum memory will enable the implementation of large-scale quantum systems for real-life applications. Due to either intrinsic high noises or short lifetime, it is still challenging to find a room-temperature broadband quantum memory beyond conceptual demonstration. Here, we present a far-off-resonance Duan-Lukin-Cirac-Zoller (FORD) protocol and demonstrate the broadband quantum memory in room-temperature atoms. We observe a low unconditional noise level of $10^{-4}$ and a cross-correlation up to 28. A strong violation of Cauchy-Schwarz inequality indicates high-fidelity generation and preservation of non-classical correlation. Furthermore, the achieved cross-correlation in room-temperature atoms exceeds the key boundary of 6 above which quantum correlation is able to violate Bell's inequality. Our results open up the door to an entirely new realm of memory-enabled quantum applications at ambient conditions.

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Jian-Peng Dou, Ai-Lin Yang, Mu-Yan Du, Di Lao, Jun Gao, Lu-Feng Qiao, Hang Li, Xiao-Ling Pang, Zhen Feng, Hao Tang, Xian-Min Jin. 2017-04-20. A Broadband DLCZ Quantum Memory in Room-Temperature Atoms. https://doi.org/10.1038/s42005-018-0057-9

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