International Journal of

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In this paper, we study the entanglement of two-level atoms near a spherical silver nanoparticle. By employing the Von Neumann equation and utilizing of the electromagnetic Green’s tensor associated with a dispersive and dissipative dielectric sphere, the decay rates and the Lamb shift of the atomic system are obtained. Then, by using the concurrence measure, we calculate the degree of entanglement of the atomic system. We observe that the decay rates severely increase near the excitation frequency of the localized plasmon-polariton, while the concurrence value is nearly zero.
 
 

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ABSTRACT—One of the nonlinear optical phenomena which arise out of a χ⁽³⁾ nonlinearity, is the intensity dependence of the refractive index. In this paper, we describe this phenomenon based on the nonlinear coherent states approach. We show that the deformed two-dimensional oscillator algebra can be used to describe this nonlinear optical system. Then, we construct the nonlinear coherent states for this nonlinear optical system and study their quantum statistical properties. Finally, we find that by changing nonlinearity of the media, it is possible to control the nonclassical properties of the system.