Study On Interaction And Propagation Characteristics Of Lattice Solitons

The self-trapping of beam in periodic photonic structures, which has become one of the focuses of the subject of optical solitons in recent years, exhibits wide prospects of application in all optical drive, optical switch and optical communication. Especially, the property of optical lattice shows a wealth of opportunities for designing various photonic devices. In this paper, the interaction of optical lattice soliton and the characteristics of two-order lattice soliton's propagation are investigated in Kerr-type nonlinear medium with transverse periodic modulation of refractive index analytically and numerically. And some innovative research results have been worked out. It includes mainly as following parts:Firstly, it is investigated how the media parameter and incidence angle affect the characteristics of two-order lattice soliton's propagation in one-dimension optical lattice. Based on the theoretical mode of nonlinear Schr?dinger equation followed by beam in Kerr-type nonlinear medium with transverse periodic modulation of refractive index, the decay rule of two-order soliton is investigated numerically. We found that the bound states of two-order soliton decayed into two fundamental solitons with different amplitudes under the influence of periodic modulation. The fundamental soliton with big amplitude is trapped in a guide-like channel whereas the one with small amplitude moves across the periodic potential when the incident angle is less than a certain critical value, or one of the modulation depth and modulation period is above a certain critical value. On the contrary, both of the fundamental solitons will move across the potential.Secondly, the effect of media parameter and beam parameter on interaction of optical lattice soliton is investigated analytically and numerically. The propagation conditions and equations, which govern the evolution of the soliton interaction, are obtained. It is found that the period of soliton interaction is varying with modulation period and modulation depth when the double beam is in the same potential. In this case the lattice soliton interaction is effectively avoided by opposite phase soliton. Otherwise, the double beams will oscillate periodically instead of collision around the centre of their own potential due to the effect of transverse periodic modulation of refractive index.