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arXiv · 0909.2342

Bound entanglement in quantum phase transitions

S. Baghbanzadeh·S. Alipour·A. T. Rezakhani
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Abstract

We investigate quantum phase transitions in which a change in the type of entanglement from bound entanglement to either free entanglement or separability may occur. In particular, we present a theoretical method to construct a class of quantum spin-chain Hamiltonians that exhibit this type of quantum criticality. Given parameter-dependent two-site reduced density matrices (with prescribed entanglement properties), we lay out a reverse construction for a compatible pure state for the whole system, as well as a class of Hamiltonians for which this pure state is a ground state. This construction is illustrated through several examples.

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S. Baghbanzadeh, S. Alipour, A. T. Rezakhani. 2010-04-06. Bound entanglement in quantum phase transitions. https://doi.org/10.1103/physreva.81.042302

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