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arXiv · 0803.1499

Multipartite Entanglement in Non-Equilibrium Quantum Phase Transition in a Collective Atomic System

Kishore T. Kapale·Girish S. Agarwal
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Abstract

We study multipartite entanglement in non-equilibrium quantum phase transition (NEQPT) attainable in a coherently driven atomic ensemble undergoing collective decay. The NEQPT arises in the steady state of the system as the drive field strength is varied in comparison with the decay parameter. A close connection is observed between the critical behavior and the multi-partite entanglement in the system determined via the von Neumann entropy. The derivative of the von Neumann entropy shows Lambda-type behavior typical of the second order phase transitions. We further show that the calculated bi- and tri- partite entropies satisfy the Lieb inequality.

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Kishore T. Kapale, Girish S. Agarwal. 2008-03-10. Multipartite Entanglement in Non-Equilibrium Quantum Phase Transition in a Collective Atomic System. https://arxiv.org/abs/0803.1499

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