Bell-type correlations from continuous variable measurements

Timothy C. Ralph, William J. Munro, Rodney Polkinghorne

We show theoretically that Bell-type correlations can be observed between continuous variable measurements performed on a parametric source. An auxiliary measurement, performed on the detection environment, negates the possibility of constructing a local realistic description of these correlations.

Takanori Sugiyama

Elanor H. Huntington, Timothy C. Ralph

Summary form only given. Drawing on recent advances in the treatment of continuous variable systems, we propose two systems that can be used to observe Bell-type correlations between the continuous variables of their sub-systems. A set of polarisation dependent measurements of the quadrature amplitude and phase of a system can be used to construct a correlation parameter that we shall denote B. We take B > 2 to indicate Bell-type (or strong, nonclassical) correlations, which may be used as a resource in quantum information experiments.

Ämin Baumeler, Julien Degorre, Stefan Wolf

Afshin Shafiee, Reza Maleeh, Mehdi Golshani

Timothy C. Ralph, William J. Munro

Recently K. Banaszek, I. A. Walmsley, K. Wodkiewicz (quant-ph/0012097) commented on our Proposal for the Measurement of Bell-Type Correlations from Continuous Variables [T. C. Ralph, W. J. Munro, R. E. S. Polkinghorne, Phys. Rev. Lett. 85, 2035 (2000)]. Their comment is based on a blatant misreading and misunderstanding of our letter and as such is simply wrong.