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arXiv:quant-ph/0410194 · Journal of Optics B Quantum and Semiclassical Optics

Nonlocality of two- and three-mode continuous variable systems

Alessandro Ferraro, Matteo G A Paris

Published May 17, 2005• 38 citations
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Abstract

We address the nonlocality of fully inseparable three-mode Gaussian states generated either by bilinear three-mode Hamiltonians or by a sequence of bilinear two-mode Hamiltonians. Two different tests revealing nonlocality are considered, in which the dichotomic Bell operator is represented by the displaced parity and by the pseudospin operator respectively. Three-mode states are also considered as a conditional source of two-mode non-Gaussian states, whose nonlocality properties are analysed. We found that the non-Gaussian character of the conditional states allows violation of Bell's inequalities (by parity and pseudospin tests) stronger than with a conventional twin-beam state. However, the non-Gaussian character is not sufficient to reveal nonlocality through a dichotomized quadrature measurement strategy.

DOI
10.1088/1464-4266/7/6/003

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