Son W, Brukner C, Kim M S
School of Mathematics and Physics, The Queen's University, Belfast BT7 1NN, United Kingdom.
Phys Rev Lett. 2006 Sep 15;97(11):110401. doi: 10.1103/PhysRevLett.97.110401. Epub 2006 Sep 11.
We propose a scheme to test Bell's inequalities for an arbitrary number of measurement outcomes on entangled continuous-variable (CV) states. The Bell correlation functions are expressible in terms of phase-space quasiprobability functions with complex ordering parameters, which can experimentally be determined via a local CV-qubit interaction. We demonstrate that CV systems can give higher violations of these Bell's inequalities than of the ones developed for two-outcome observables.