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arXiv · 1610.07820

Biseparability of 3-qubits density matrices using Hilbert-Schmidt decompositions: Sufficient conditions and explicit expressions

Y. Ben-Aryeh·A. Mann
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Abstract

Hilbert-Schmidt (HS) decompositions and Frobenius norms are used to analyze biseparability of 3-qubit systems, with particular emphasis on density matrices with maximally disordered subsystems (MDS) and on the W state mixed with white noise. The biseparable form of a MDS density matrix is obtained by using the Bell states of a 2-qubit subsystem, multiplied by density matrices of the third qubit, which include the relevant HS parameters. Using our methods a sufficient condition and explicit biseparability of the W state mixed with white noise are given. They are compared with the sufficient condition for explicit full separability given in a previous work.

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Y. Ben-Aryeh, A. Mann. 2016-10-25. Biseparability of 3-qubits density matrices using Hilbert-Schmidt decompositions: Sufficient conditions and explicit expressions. https://arxiv.org/abs/1610.07820

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