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A new conception experimental test of Bell inequalities using non-maximally entangled states

G. Brida·M. Genovese·C. Novero·E. Predazzi
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Abstract

We report on a test of Bell inequalities using a non-maximally entangled state, which represents an important step in the direction of eliminating the detection loophole. The experiment is based on the creation of a polarisation entangled state via the superposition, by use of an appropriate optics, of the spontaneous fluorescence emitted by two non-linear crystals driven by the same pumping laser. The alignment has profitably taken advantage from the use of an optical amplifier scheme, where a solid state laser is injected into the crystals together with the pumping laser. In principle a very high total quantum efficiency can be reached using this configuration and thus the final version of this experiment can lead to a resolution of the detection loophole, we carefully discuss the conditions which must be satisfied for reaching this result.

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G. Brida, M. Genovese, C. Novero, E. Predazzi. 2000-04-07. A new conception experimental test of Bell inequalities using non-maximally entangled states. https://arxiv.org/abs/quant-ph/0004033

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