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Quantum Superposition of Parametrically Amplified Multiphoton Pure States whitin a Decoherence-Free Schroedinger-Cat Structure

F. A. Bovino·F. De Martini·V. Mussi
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Abstract

The new process of quantum-injection into an optical parametric amplifier operating in entangled configuration is adopted to amplify into a large dimensionality spin 1/2 Hilbert space the quantum entanglement and superposition properties of the photon-couples generated by parametric down-conversion. The structure of the Wigner function and of the field's correlation functions shows a decoherence-free, multiphoton Schroedinger-cat behaviour of the emitted field which is largely detectable against the squeezed-vacuum noise. Furthermore, owing to its entanglement character, the system is found to exhibit multi-particle quantum nonseparability and Bell-type nonlocality properties. These relevant quantum features are analyzed for several travelling-wave optical configurations implying different input quantum-injection schemes

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F. A. Bovino, F. De Martini, V. Mussi. 1999-05-14. Quantum Superposition of Parametrically Amplified Multiphoton Pure States whitin a Decoherence-Free Schroedinger-Cat Structure. https://arxiv.org/abs/quant-ph/9905048

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