انجمن اپتیک و فوتونیک ایران

Entanglement between a Two-level Atom and the Coherent Photonic States in a Nonlinear Cavity

Mohammad Reza Abbasi

Published Feb 15, 2014• 0 citations

Abstract

In this paper the time evolution of von Neumann entropy as a measure of entanglement between a two-level atom and the photonic coherent states in a cavity is studied. The atom-photon interaction occurs in the presence of a centrosymmetric medium which makes the photonic cavity mode couple with itself via the third order susceptibility. In the present system the atom-photon interaction is assumed to follow the linear Jaynes-Cummings model while the photonic selfcoupling is due to presence of a centrosymmetric medium and occurs via the third order susceptibility. After calculating the time-evolution operator, the von Neumann entropy, as a function of time, is determined. It is shown that an increase of photonic self-coupling leads to decreasing of entanglement. Furthermore, the role of atom-photon detuning on the entanglement behavior is also addressed.

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