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arXiv · 0808.1934

Division of the two-qubit Hilbert space according to the entanglement sudden death under composite noise environment

Peng Li·Qun Zhang·J. Q. You
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Abstract

We show theoretically that according to the disentanglement behavior under composite noise environment, the Hilbert space of a two-qubit system can be divided into two separate parts: a 3-dimensional subspace in which all states disentangle asymptotically, and the rest in which all states disentangle abruptly. The violation of additivity for entanglement decay rates under weak noises [see, PRL 97, 140403 (2006)] therefore can be explained in terms of such division of the Hilbert space.

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Peng Li, Qun Zhang, J. Q. You. 2008-10-05. Division of the two-qubit Hilbert space according to the entanglement sudden death under composite noise environment. https://doi.org/10.1103/physreva.79.014303

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