الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In this thesis, which consists of an introduction and .ve chapters, we study several effects on quantum information and quantum entanglement through, the interaction between atomic systems described by one or two two-level atoms and quantized radiation field, with one or two modes.
In chapter 1, we give an overview of quantum information theory, its importance, history and development in the first section. In the following sections we introduce qubit, density operator, and quantum entanglement, some measures of entanglement for bipartite system such as von Neumann entropy, negativity, Quantum discord (QD), Geometric measure of Quantum Discord (GMQD), Measurement-Induced Disturbance (MID) and discuss Nitrogen-Vacancy Centers in Diamond.
In chapter 2, an analytical description for the dynamics of an open system of two qubits interacting with independent environments is obtained. The effect of squeezing angle on entanglement and quantum discord are considered.
In chapter 3, our motivation is to quantify the quantum correlation by (MID) and (GMQD), negativity and concurrence, and show what is the difference between them and study how the system parameters can control the dynamics of quantum correlation over the proposed model.
In chapter 4, we investigate dynamics of a dissipative system consisting of two nitrogen-
vacancy (N-V ) centers embedded in two spatially separated single-mode nanocavities
in a planar photonic crystal (PC). We solve the time-dependent Schrödinger equation
analytically for arbitrary values of the hopping and PC.N-V coupling strengths. We have
also analyzed the relevant entanglement dynamics in the presence of decoherence.
In chapter 5, we introduced the Pancharatnam phase for isotropic coupled oscillator
prepared initially in the excited state. Furthermore, we have explored the influence of the detuning parameter, the ratio of the coupling parameters and other parameter on the Pancharatnam phase.
Finally in chapter 6, we conclude our work where we summarize all the results achieved
from the previous chapters and introduce an outlook for a future work.