Another convex combination of product states for the separable Werner state Hiroo Azuma
نویسندگان
چکیده
In this paper, we write down the separable Werner state in a two-qubit system explicitly as a convex combination of product states, which is different from the convex combination obtained byWootters’ method. TheWerner state in a two-qubit system has a single real parameter and varies from inseparable state to separable state according to the value of its parameter. We derive a hidden variable model that is induced by our decomposed form for the separable Werner state. From our explicit form of the convex combination of product states, we understand the following: The critical point of the parameter for separability of the Werner state comes from positivity of local density operators of the qubits.
منابع مشابه
ua nt - p h / 06 01 04 4 v 1 7 J an 2 00 6 A convex combination of product states for the separable Werner state
In this paper, we write down the separable Werner state in a two-qubit system as a convex combination of product states explicitly. The Werner state in a two-qubit system has a single real parameter and varies from inseparable state to separable state according to the value of its parameter. The convex combination of product states gives a hidden variable model to the separable Werner state.
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