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arXiv · 2006.16439

Negativity of the Wigner function and thermal effects of Bell-Cat states

Vinícius N. A. Lula-Rocha·Sergio Floquet·Marco A. S. Trindade·Marco C. B. Fernandes·José D. M. Vianna
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Abstract

We applied the Thermofield Dynamics formalism to analyze how the non-classical properties of the Bell-Cat states are influenced by a gradual change of temperature values, in a thermal equilibrium system. To this purpose we calculate the thermal Wigner functions for these states, whose negative volume is associated with non-classical properties, and we evaluate how these non-classical features vary with temperature. Our results indicate that these properties are almost absent for temperatures of around $2\mathrm{K}$.

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Vinícius N. A. Lula-Rocha, Sergio Floquet, Marco A. S. Trindade, Marco C. B. Fernandes, José D. M. Vianna. 2020-06-30. Negativity of the Wigner function and thermal effects of Bell-Cat states. https://arxiv.org/abs/2006.16439

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