On maximal entanglement between two pairs in four - qubit pure states
نویسنده
چکیده
We show that the state with the highest known average two-particle von Neumann entanglement entropy proposed by Sudbery and one of the authors gives a local maximum of this entropy. We also show that this is not the case for an alternative highly entangled state proposed by Brown et al.
منابع مشابه
How entangled can two couples get ?
We describe a pure state of four qubits whose single-qubit density matrices are all maximally mixed and whose average entanglement as a system of two pairs of qubits appears to be maximal.
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تاریخ انتشار 2007