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Homodyne Bell's inequalities for entangled mesoscopic superpositions

Andrzej Dragan·Konrad Banaszek
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Abstract

We present a scheme for demonstrating violation of Bell's inequalities using a spin-1/2 system entangled with a pair of classically distinguishable wave packets in a harmonic potential. In the optical domain, such wave packets can be represented by coherent states of a single light mode. The proposed scheme involves standard spin-1/2 projections and measurements of the position and the momentum of the harmonic oscillator system, which for a light mode can be realized by means of homodyne detection. We discuss effects of imperfections, including non-unit efficiency of the homodyne detector, and point out a close link between the visibility of interference and violation of Bell's inequalities in the described scheme.

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Andrzej Dragan, Konrad Banaszek. 2001-10-23. Homodyne Bell's inequalities for entangled mesoscopic superpositions. https://doi.org/10.1103/physreva.63.062102

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