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Entanglement Sharing and Decoherence in the Spin-Bath

Christopher M. Dawson·Andrew P. Hines·Ross H. McKenzie·G. J. Milburn
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Abstract

The monogamous nature of entanglement has been illustrated by the derivation of entanglement sharing inequalities - bounds on the amount of entanglement that can be shared amongst the various parts of a multipartite system. Motivated by recent studies of decoherence, we demonstrate an interesting manifestation of this phenomena that arises in system-environment models where there exists interactions between the modes or subsystems of the environment. We investigate this phenomena in the spin-bath environment, constructing an entanglement sharing inequality bounding the entanglement between a central spin and the environment in terms of the pairwise entanglement between individual bath spins. The relation of this result to decoherence will be illustrated using simplified system-bath models of decoherence.

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Christopher M. Dawson, Andrew P. Hines, Ross H. McKenzie, G. J. Milburn. 2005-03-10. Entanglement Sharing and Decoherence in the Spin-Bath. https://doi.org/10.1103/physreva.71.052321

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