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arXiv · 1906.03769

Nonlocality test of energy-time entanglement via nonlocal dispersion cancellation with nonlocal detection

Baihong Li·Feiyan Hou·Runai Quan·Ruifang Dong·Lixing You·Hao Li·Xiao Xiang·Tao Liu·Shougang Zhang
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Abstract

Energy-time entangled biphoton source plays a great role in quantum communication, quantum metrology and quantum cryptography due to its strong temporal correlation and capability of nonlocal dispersion cancellation. As a quantum effect, nonlocal dispersion cancellation is further proposed as an alternative way for nonlocality test of continuous variable entanglement via the violation of Bell-like inequality proposed by Wasak et al. [Phys. Rev. A, 82, 052120 (2010)]. However, to date there is no experimental report either on the inequality violation or on a nonlocal detection with single-photon detectors at long-distance transmission channel, which is key for a true nonlocality test. In this paper, we report an experimental realization of a violation of the inequality after 62km optical fiber transmission at telecom wavelength with a nonlocal detection based on event timers and cross-correlation algorithm, which indicates a successful nonlocal test of energy-time entanglement. This work provides a new feasibility for the strict test of the nonlocality for continuous variables in both long-distance communication fiber channel and free space.

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Baihong Li, Feiyan Hou, Runai Quan, Ruifang Dong, Lixing You, Hao Li, Xiao Xiang, Tao Liu, Shougang Zhang. 2019-06-10. Nonlocality test of energy-time entanglement via nonlocal dispersion cancellation with nonlocal detection. https://doi.org/10.1103/physreva.100.053803

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