English

Nonlocality of two- and three-mode continuous variable systems

Quantum Physics 2009-11-10 v2

Abstract

We address nonlocality of a class 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 strong nonlocality are considered, in which the dichotomic Bell operator is represented by displaced parity and by pseudospin operator respectively. Three-mode states are also considered as a conditional source of two-mode non Gaussian states, whose nonlocal properties are analyzed. 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 thorough a dichotomized quadrature measurement strategy.

Keywords

Cite

@article{arxiv.quant-ph/0410194,
  title  = {Nonlocality of two- and three-mode continuous variable systems},
  author = {A. Ferraro and M. G. A. Paris},
  journal= {arXiv preprint arXiv:quant-ph/0410194},
  year   = {2009}
}

Comments

17 pages, 7 figures. A paragraph concerning the choice of the displacement parameters has been added (Sec. 3.1). References and comparison with other proposals added (Sec. 4)