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Decoherence and Entanglement in Two-mode Squeezed Vacuum States

Tohya Hiroshima
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Abstract

I investigate the decoherence of two-mode squeezed vacuum states by analyzing the relative entropy of entanglement. I consider two sources of decoherence: (i) the phase damping and (ii) the amplitude damping due to the coupling to the thermal environment. In particular, I give the exact value of the relative entropy of entanglement for the phase damping model. For the amplitude damping model, I give an upper bound for the relative entropy of entanglement, which turns out to be a good approximation for the entanglement measure in usual experimental situations.

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Tohya Hiroshima. 2000-06-22. Decoherence and Entanglement in Two-mode Squeezed Vacuum States. https://doi.org/10.1103/physreva.63.022305

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