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arXiv · 1309.2033

Violation of Bell-CHSH inequality using imperfect photodetectors with optical hybrid states

Hyukjoon Kwon·Hyunseok Jeong
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Abstract

We show that a Bell inequality test using an optical hybrid state between a polarized single photon and a coherent field can be highly robust against detection inefficiency. The Bell violation occurs until the efficiency becomes as low as 67% even though its degree becomes small as the detection efficiency degrades. We consider on/off and photon number parity measurements, respectively, for the Bell test and they result in the similar conditions. If the detection efficiency is higher than 98.68%, parity measurements give larger Bell violations close to Cirel'son's bound, while on/off measurements give larger but moderate violations for realistic values of detector efficiency. Experimental realization of our proposal seems feasible in the near future for the implementation of a loophole-free Bell inequality test.

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Hyukjoon Kwon, Hyunseok Jeong. 2013-11-08. Violation of Bell-CHSH inequality using imperfect photodetectors with optical hybrid states. https://doi.org/10.1103/physreva.88.052127

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