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arXiv · 1407.7716

Tripartite entanglement dynamics and entropic squeezing of a three-level atom interacting with a bimodal cavity field

M. J. Faghihi·M. K. Tavassoly·M. Bagheri Harouni
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Abstract

In this paper, we study the interaction between a $Λ$-type three-level atom and two quantized electromagnetic fields which are simultaneously injected in a bichromatic cavity surrounded by a Kerr medium in the presence of the field-field interaction (parametric down conversion) and detuning parameters. By applying a canonical transformation, the introduced model is reduced to a well-known form of the generalized Jaynes-Cummings model. Under particular initial conditions which may be prepared for the atom and the field, the time evolution of state vector of the entire system is analytically evaluated. Then, the dynamics of atom is studied through the evolution of the atomic population inversion. In addition, two different measures of entanglement between the tripartite system (three entities make the system: two field modes and one atom) i.e., von Neumann and linear entropy are investigated. Also, two kinds of entropic uncertainty relations, from which entropy squeezing can be obtained, are discussed. In each case, the influences of the detuning parameters and Kerr medium on the above nonclassicality features are analyzed via numerical results, in detail. It is illustrated that the amount of the above-mentioned physical phenomena can be tuned by choosing the evolved parameters, appropriately.

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M. J. Faghihi, M. K. Tavassoly, M. Bagheri Harouni. 2014-07-29. Tripartite entanglement dynamics and entropic squeezing of a three-level atom interacting with a bimodal cavity field. https://doi.org/10.1088/1054-660x%2F24%2F4%2F045202

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