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arXiv · 0905.4652

Sudden Death and Birth of Entanglement Effects for Kerr-Nonlinear Coupler

A. Kowalewska-Kudłaszyk·W. Leoński
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Abstract

We analyse the entanglement dynamics in a nonlinear Kerr-like coupler interacting with external environment. Whenever the reservoir is in a thermal vacuum state the entanglement (measured by concurrence for a two-qubit system) exhibits regular oscillations of decreasing amplitude. In contrast, for thermal reservoirs we can observe dark periods in concurrence oscillations (which can be called a "sudden death" of the entanglement) and the entanglement rebuild (which can be named the "sudden birth" of entanglement). We show that these features can be observed when we deal with 2-qubit system as well as $2\otimes 3$ system.

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A. Kowalewska-Kudłaszyk, W. Leoński. 2009-05-28. Sudden Death and Birth of Entanglement Effects for Kerr-Nonlinear Coupler. https://doi.org/10.1364/josab.26.001289

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