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arXiv · 0804.0341

Entanglement and Non-locality in a Micro-Macroscopic system

Francesco De Martini·Fabio Sciarrino·Chiara Vitelli
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Abstract

In recent years two fundamental aspects of quantum mechanics have attracted a great deal of interest, namely the investigation on the irreducible nonlocal properties of Nature implied by quantum entanglement and the physical realization of the 'Schroedinger Cat'. In the present work a macro - state consisting of about 3.5 x 10^4 photons in a quantum superposition and entangled with a far apart single - photon state is generated. Then, the non-separability of the overall micro-macro system is demonstrated and the corresponding Bell's inequalities are found to be violated. Precisely, an entangled photon pair is created by a nonlinear optical process, then one photon of the pair is injected into an optical parametric amplifier operating for any input polarization state, i.e. into a phase-covariant cloning machine. Such transformation establishes a connection between the single photon and the multi particle fields. We then demonstrate the non-separability of the bipartite system by adopting a local filtering technique within a positive operator valued measurement.

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Francesco De Martini, Fabio Sciarrino, Chiara Vitelli. 2008-04-02. Entanglement and Non-locality in a Micro-Macroscopic system. https://arxiv.org/abs/0804.0341

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