Nonlocal Spatial Optical Soliton Polarization Coupling

Spatial optical solitons may provide a powerful means for creating reconfigurable all-optical cirtcuits where light is guided and controlled by itself. In recent years, optical solitons in nonlocal nonlinear media have become the subject of intense studies. The propagation of optical beams in the nonlocal nonlinear media is modeled by the nonlocal nonlinear Schrodinger equation (NNLSE). It has been theoretically and experimentally demonstrated that nonlocal spatial optical solitons have more rich phenomena and potential applications compared to local solitons. However, most of the investigation is based on one-polarized light beam. This dissertation focus on the propagation of two orthogonally polarized light beams in nonlocal Kerr-like planar waveguide.The main innovation and conclusion are as follows:( 1 ) Based on Maxwell Equations, the evolution equations of TE and TM-polarized light beams in nonlocal nonlinear planar waveguide are derived using waveguide theory. The polarization-coupling model of light beams is derived by expanding the intensity profile with talor series. Then the Lagrange function of the model is obtained.(2)The propagation of two orthogonally polarized coaxial light beams in nonlocal Kerr-like planar waveguides is studied by variational principle well as numerical method. The evolution equations of beam width, phase-front curvature, amplitude and phase are derived provided that the beam profile is of Gaussian function form. The way how the coupling coefficient, the degree of nonlocality and linear birefregence affect the propagation of the two beams is discussed. The condition for soliton-like mutually-trapped propagation of the two beams is obtained. Nonlocal vector spatial solitons exist if only the waveguide parameters equal to certain value. Then a numerical simulation is implemented, which confirms that the true soliton dynamics qualitatively agree with the mathematical analysis.(3)The interaction of polarization-coupled spatial solitons in nonlocal Kerr-like planar waveguides is investigated, using variational principle. The curve is obtained which depicts the potential of the two solitons versus the net displacement between them. A numerical simulation for the interaction is implemented, which confirms the results of the previous mathematical analysis. The conclusion is that as the degree of nonlocality increases, the incoherent interaction of the beam pair enhances.