Propagation Properties Of Solitons In The Strongly Nonlocal Nonlinear Media

Since the first Roby laser was born in1960, laser optics has experienced a fastdevelopment.The propagating beam becomes self-trapping in nonlinear media because of thecompression of beam that originated from the interaction between the beam and the nonlinear media.At the same time, the diffraction of the propagating the beam would lead to its broadening.Soliton,achieved with the balance between the compression and the the broadening effect,can realizeself–guiding and steady propagation.These optical solitons can control signal light, and realizeoptical device, such as photonic switching and logic gating etc. Therefore, spatial solitons have beena hot topic in nonlinear optical field. However, most study of spatial solitons is limited in localnonlinear media.This thesis focuses on soliton propagation in strongly nonlocal nonlinear media and theirinteraction. The theis is structured as follows:In Chapter1, the research progress of soliton is reviewed, and the experimental and theortical studieson the spatial optical soliton in the strongly nonlocal nonlinear media in recent years are summarized.In Chapter2, basing on the accurate Gaussian analytical solution of a pair of (1+2)D optical spatialsolitons with symmetrical oblique incidence, we investigate the short~range interactions in thestrongly nonlocal nonlinear media. During propagating in nonlocal nonlinear media, two solitons inclose proximity can be intertraped via the strong nonlocality.The trajectory of mass center of solitonswill deflect because of the phase difference and the ratio of the power of two solitons under thecondition of momentum conservation. It is possible to find its applications in planar all~opticalinterconnection in bulk media. We analyzes the evolution of the Poynting vector as they propagatethrough the strongly nonlocal media.In Chapter3, We discuss the propagating of (1+1)D and (1+2)D beams in SNNM in Cartesiancoordinate, and the solutions of EHGBs with modulating the Gaussian beam by the parabolic cylinderfunctions have been obtained. Two collinear elegant Hermite-Gaussian beams evolve vortex beams onthe certain condition. The propagation of the single EHGBs and the collinear vortex EHGBs at thecritic power are given. the sizes of their profiles become periodic in the propagation, and thebreathers and the rotating vortex breathers are accessed.In Chapter4, The optical fields that are produced by two collinear Laguerre-Gaussian solitons (LGs)in the strongly nonlocal nonlinear media are studied based on the modified Snyder-Mitchell model.Various solitons appeared on the profiles, which depending on the model-index and the relative amplitude of LGs. It is phase vortices of the LGs that lead to the optical singularities. Many ring~likesoliton and the optical vortex soliton are accessed firstly with the superposition LGs. The optical fieldmay rotates in the propagation because of the gouy phase and the angular velocity of the spiralsoliton.In Chapter5, We discuss the propagating of beams in SNNM in Elliptic coordinate, and thesolutions of EHGBs with modulating the Gaussian beam by Ince polynomials have been obtained.Ince~Gaussian beams will evolve the solitons at the critic power; otherwise, they will evolvebreathers. the profiles of the breather to the different propagating distance are numerically obtained.On the certain condition, ince-Gaussian beams constitute the exact and continuous transition modesbetween Hermite-Gaussian beams and Laguerre-Gaussian beams.