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arXiv · 0911.4158

Saving Entanglement via a Nonuniform Sequence of $π$ Pulses

G. S. Agarwal
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Abstract

We examine the question of survival of quantum entanglement between the bipartite states and multiparticle states like GHZ states under the action of a dephasing bath by the application of sequence of $π$ pulses. We show the great advantage of the pulse sequence of Uhrig [ 2007 {\it Phys. Rev. Lett.} {\bf 98} 100504] applied at irregular intervals of time, in controlling quantum entanglement. In particular death of entanglement could be considerably delayed by pulses. We use quantum optical techniques to obtain exact results.

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G. S. Agarwal. 2010-08-24. Saving Entanglement via a Nonuniform Sequence of $π$ Pulses. https://doi.org/10.1088/0031-8949%2F82%2F03%2F038103

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