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On the realization of Bell observables

Giacomo Mauro D'Ariano·Paolo Perinotti
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Abstract

We show how Bell observables on a bipartite quantum system can be obtained by local observables via a controlled-unitary transformation. For continuous variables this result holds for the Bell observable corresponding to the non-conventional heterodyne measurement on two radiation modes, which is connected through a 50-50 beam-splitter to two local observables given by single-mode homodyne measurements. A simple scheme for a controlled-unitary transformation of continuous variables is also presented, which needs only two squeezers, a parametric downconverter and two beam splitters.

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Giacomo Mauro D'Ariano, Paolo Perinotti. 2004-06-11. On the realization of Bell observables. https://doi.org/10.1016/j.physleta.2004.07.006

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