Researches On Strongly Nonlocal Spatial Optical Solitons And Their Interaction

In this paper, discussed is the evolution and the interaction of optical beams in nonlocal Kerr media, governed by the nonlocal nonlinear Schrodinger equation (NNLSE).The paper is organized as follows:Chapter 1, we present an overview of recent advances in the researches of optical beam propagating in nonolocal nonlinear media.Chapter 2, we discuss the evolution of the off-waist incident Gaussian beam in the nonlocal nonlinear media by use of the (1+1)-dimensional strongly nonlocal model. An exact analytical solution for the evolution is obtained. We find that no matter how high the power of the incident beam is, no spatial soliton will exist. The definition of a "spatial chirp" is given, to our knowledge, for the first time. The physical origin of the phenomenon above is that the different incident position corresponds to the different spatial chirp.Chaper 3, We use the Snyder-Mitchell model to explore the interaction in the symmetrical configuration, as well as that of two solitons with different intensity through proper coordinate transformations, and analytical solutions are obtained.Chapter 4, NNLSE is simulated for two beam propagation. The comparisons of our analytical solutions with numerical simulations of the NNLSE show that the analytical solutions are in agreement with the numerical simulations.The main achievement of the paper is that no matter how high the power of the incident beam is no spatial soliton will exist, when the Gaussian beam is off-waist incident in the nonlocal nonlinear media. The definition of a "spatial chirp" is given, to our knowledge, for the first time. The physical origin of the phenomenon above is that the different incident position corresponds to the different spatial chirp. We use the Snyder-Mitchell model to explore the interaction in the symmetrical configuration, as well as that of two solitons with different intensity through proper coordinate transformations.