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arXiv · 1108.2681

Effect of Interatomic Separation on Entanglement Dynamics in a Two-Atom Two-Mode Model

K. Sinha·N. I. Cummings·B. L. Hu
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Abstract

We analyze the time evolution of quantum entanglement in a model consisting of two two-level atoms interacting with a two-mode electromagnetic field for a variety of initial states and interatomic separations. We study two specific atomic separations which give rise to symmetric atom-field couplings. For general atomic distances we consider a subset of initial states analytically, and then treat the more general situation numerically. We examine a variety of qualitative features such as entanglement sudden death, dynamical generation, protection, and transfer between subsystems. Our analysis shows a stark contrast in features of entanglement between the two special coupling schemes often considered; further, these features are uncharacteristic of those arising for general distances, due to the high degree of symmetry present in the special cases. The variety of behaviors in these two-mode cases suggest the importance of considering atomic separation carefully for any model where two atoms interact with a common field.

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K. Sinha, N. I. Cummings, B. L. Hu. 2011-08-12. Effect of Interatomic Separation on Entanglement Dynamics in a Two-Atom Two-Mode Model. https://doi.org/10.1088/0953-4075/45/3/035503

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