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arXiv · 1208.2706

Genuinely Multipartite Concurrence of N-qubit X-matrices

S. M. Hashemi Rafsanjani·M. Huber·C. J. Broadbent·J. H. Eberly
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Abstract

We find an algebraic formula for the N-partite concurrence of N qubits in an X-matrix. X- matricies are density matrices whose only non-zero elements are diagonal or anti-diagonal when written in an orthonormal basis. We use our formula to study the dynamics of the N-partite entanglement of N remote qubits in generalized N-party Greenberger-Horne-Zeilinger (GHZ) states. We study the case when each qubit interacts with a partner harmonic oscillator. It is shown that only one type of GHZ state is prone to entanglement sudden death; for the rest, N-partite entanglement dies out momentarily. Algebraic formulas for the entanglement dynamics are given in both cases.

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S. M. Hashemi Rafsanjani, M. Huber, C. J. Broadbent, J. H. Eberly. 2012-08-13. Genuinely Multipartite Concurrence of N-qubit X-matrices. https://doi.org/10.1103/physreva.86.062303

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