Genuinely multipartite concurrence of N -qubit X matrices
Genuinely multipartite concurrence of N -qubit X matrices
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DOI：
10.1103/physreva.86.062303
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发表时间：
2012-08
影响因子：
2.9
通讯作者：
S. Rafsanjani;M. Huber;C. Broadbent;J. Eberly
中科院分区：
文献类型：
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作者：
S. Rafsanjani;M. Huber;C. Broadbent;J. Eberly
我们发现了一个代数公式的N-部并发的N个量子比特在一个X矩阵。X矩阵是密度矩阵，其唯一的非零元素是对角或反对角时，写在正交基。利用我们的公式研究了N个远程量子比特在广义N方Greenberger-Horne-Zeilinger（GHZ）态中的N方纠缠动力学，研究了量子比特与局域振幅阻尼通道相互作用的情况.结果表明，只有一种GHZ态在有限时间内失去纠缠，其余的N-体纠缠渐近消失。在这两种情况下的纠缠动力学的代数公式。我们直接证实了纠缠的半衰期与N的倒数成正比。当纠缠在有限时间内消失时，纠缠消失的时间可以随N的增加而减少，也可以随N的增加而增加，这取决于初始状态。在宏观极限下，这个时间与初始纠缠无关。
We find an algebraic formula for the N-partite concurrence of N qubits in an X matrix. X matrices are density matrices whose only nonzero elements are diagonal or antidiagonal 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.Westudythecaseinwhicheachqubitinteractswithalocalamplitude damping channel. It is shown that only one type of GHZ state loses its entanglement in finite time; for the rest, N-partite entanglement dies out asymptotically. Algebraic formulas for the entanglement dynamics are given in both cases. We directly confirm that the half-life of the entanglement is proportional to the inverse of N .W hen entanglement vanishes in finite time, the time at which entanglement vanishes can decrease or increase with N depending on the initial state. In the macroscopic limit, this time is independent of the initial entanglement.