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arXiv · 1206.2289

Loophole-free Bell test based on local precertification of photon's presence

Adan Cabello·Fabio Sciarrino
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Abstract

A loophole-free violation of Bell inequalities is of fundamental importance for demonstrating quantum nonlocality and long-distance device-independent secure communication. However, transmission losses represent a fundamental limitation for photonic loophole-free Bell tests. A local precertification of the presence of the photons immediately before the local measurements may solve this problem. We show that local precertification is feasible by integrating three current technologies: (i) enhanced single-photon down-conversion to locally create a flag photon, (ii) nanowire-based superconducting single-photon detectors for a fast flag detection, and (iii) superconducting transition-edge sensors to close the detection loophole. We carry out a precise space-time analysis of the proposed scheme, showing its viability and feasibility.

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Adan Cabello, Fabio Sciarrino. 2012-06-11. Loophole-free Bell test based on local precertification of photon's presence. https://doi.org/10.1103/physrevx.2.021010

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