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arXiv · 1211.7001

Pre-management of Disentanglement

Xiao-Feng Qian
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Abstract

We define threshold disentanglement (TD) as the level above which entanglement must be maintained for later use and calculate the values of quantum system parameters at $t=0$ that will ensure that the threshold is not crossed in a specified time. An important issue is the possibility of non-smooth, typically non-exponential, decay of entanglement into the state of complete disentanglement (CD). Given a specified operation time $τ$, we determine phase diagrams showing entanglement preservation during the evolution of a generic two-qubit mixed state as a function of selected initial parameters such as concurrence and excitation probabilities. In other words, disentanglement can be pre-managed through these parameters. Three common relaxation processes - amplitude, phase and depolarization - are considered.

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Xiao-Feng Qian. 2014-06-14. Pre-management of Disentanglement. https://doi.org/10.1088/1751-8113%2F47%2F26%2F265304

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