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arXiv · 2011.02807

Field demonstration of distributed quantum sensing without post-selection

Si-Ran Zhao·Yu-Zhe Zhang·Wen-Zhao Liu·Jian-Yu Guan·Weijun Zhang·Cheng-Long Li·Bing Bai·Ming-Han Li·Yang Liu·Lixing You·Jun Zhang·Jingyun Fan·Feihu Xu·Qiang Zhang·Jian-Wei Pan
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Abstract

Distributed quantum sensing can provide quantum-enhanced sensitivity beyond the shot-noise limit (SNL) for sensing spatially distributed parameters. To date, distributed quantum sensing experiments have been mostly accomplished in laboratory environments without a real space separation for the sensors. In addition, the post-selection is normally assumed to demonstrate the sensitivity advantage over the SNL. Here, we demonstrate distributed quantum sensing in field and show the unconditional violation (without post-selection) of SNL up to 0.916 dB for the field distance of 240 m. The achievement is based on a loophole free Bell test setup with entangled photon pairs at the averaged heralding efficiency of 73.88%. Moreover, to test quantum sensing in real life, we demonstrate the experiment for long distances (with 10-km fiber) together with the sensing of a completely random and unknown parameter. The results represent an important step towards a practical quantum sensing network for widespread applications.

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Si-Ran Zhao, Yu-Zhe Zhang, Wen-Zhao Liu, Jian-Yu Guan, Weijun Zhang, Cheng-Long Li, Bing Bai, Ming-Han Li, Yang Liu, Lixing You, Jun Zhang, Jingyun Fan, Feihu Xu, Qiang Zhang, Jian-Wei Pan. 2020-11-05. Field demonstration of distributed quantum sensing without post-selection. https://doi.org/10.1103/physrevx.11.031009

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