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Test of nonlocality for a continuos-variable state based on arbitrary number of measurement outcomes

W. Son·C. Brukner·M. S. Kim
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Abstract

We propose a scheme to test Bell's inequalities for an arbitrary number of measurement outcomes on entangled continuous variable states. The Bell correlation functions are expressible in terms of phase-space quasiprobability functions with complex ordering parameter, which can experimentally be determined both directly via local CV-qubit interaction or indirectly via tomographic reconstructions. We demonstrate that continuous-variable systems can give stronger violations of these Bell's inequalities than of the ones developed for two-outcome observables. Thus, while keeping the feasibility of the phase-space approach, our scheme increases its efficiency.

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W. Son, C. Brukner, M. S. Kim. 2006-09-11. Test of nonlocality for a continuos-variable state based on arbitrary number of measurement outcomes. https://doi.org/10.1103/physrevlett.97.110401

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