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Photon subtracted states and enhancement of nonlocality in the presence of noise

Stefano Olivares·Matteo G. A. Paris
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Abstract

We address nonlocality of continuous variable systems in the presence of dissipation and noise. Three nonlocality tests have been considered, based on the measurement of displaced-parity, field-quadrature and pseudospin-operator, respectively. Nonlocality of twin beam has been investigated, as well as that of its non-Gaussian counterparts obtained by inconclusive subtraction of photons. Our results indicate that: i) nonlocality of twin beam is degraded but not destroyed by noise; ii) photon subtraction enhances nonlocality in the presence of noise, especially in the low-energy regime.

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Stefano Olivares, Matteo G. A. Paris. 2005-03-10. Photon subtracted states and enhancement of nonlocality in the presence of noise. https://doi.org/10.1088/1464-4266/7/10/027

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