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arXiv · 0806.2218

Schroedinger Cat: Entanglement test in a Micro-Macroscopic system

Francesco De Martini·Fabio Sciarrino·Chiara Vitelli
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Abstract

A Macro-state consisting of N= 3.5 x 10^4 photons in a quantum superposition and entangled with a far apart single-photon state (Micro-state) is generated. 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 (OPA) 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. 2008-06-13. Schroedinger Cat: Entanglement test in a Micro-Macroscopic system. https://doi.org/10.1103/physrevlett.100.253601

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