Simultaneous amplitude and phase damping of a kind of Gaussian states and their separability
نویسنده
چکیده
We give out the time evolution solution of simultaneous amplitude and phase damping for any continuous variable state. For the simultaneous amplitude and phase damping of a wide class of twomode entangled Gaussian states, two analytical conditions of the separability are given. One is the sufficient condition of separability. The other is the condition of PPT separability where the Peres-Horodecki criterion is applied. Between the two conditions there may exist bound entanglement. The simplest example is the simultaneous amplitude and phase damping of a two-mode squeezed vacuum state. The damped state is non-Gaussian. PACS 03.65.Ud 03.65.Yz 03.67.Mn 42.50.Dv
منابع مشابه
The simultaneous amplitude and phase damping of two mode squeezed vacuum state
The Peres-Horodecki criterion of positivity under partial transpose is studied for the simultaneous amplitude and phase damping of a two mode squeezed vacuum state. The criterion turns out to be a necessary and sufficient condition for separability, although the damped state is no longer gaussian. The proof is at the sense of algebraic programming and also perturbation theory. The criterion is ...
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