The Spatial Solitons Evolvement In Photorefractive Photonic Lattice

This paper has mainly studied the dynamics of a beam in a focusing photorefractive nonlinear lattice with a longitudinal potential well and investigates the influence and control of the photonic lattice. Several situations can be concluded as follows by using finite difference method and Alternating Direction Implicit (ADI) difference method to solve (1+1)-dimensional and (2+1)-dimensional nonlinear Schrodinger equations:1. When the lattice depth reaches a certain level, the state of soliton in such kind of lattice with the refractive index modulation in both transverse and longitudinal directions will exhibit compression during transmission. The degree of compression depends on the size of the applied voltage strength. The larger the intensity of the applied voltage is, the more serious the soliton compresses. When the lattice depth matches the applied voltage intensity, soliton can maintain the prototype during transmission, Otherwise the "ripple" phenomenon will appear in the transmission process.2. When the light width can be compared with the lattice width, soliton which is incident on the lattice energy peak will be localized in the waveguide easily, while the incident soliton at the lattice lowest energy will split into two or more solitons by the impact between the adjacent waveguides.3. When the beam width is much larger than the lattice width, the refractive index modulation in transverse direction plays an important role among beam transmission. A discrete soliton will be formed in this situation, however, only if there is a good match among parameters of materials, optical lattice and signal energy, it is possible to form discrete soliton. Here, just to discuss the trend of being discrete soliton not the formation.4.(2+l)-dimensional soliton is more complex and diverse than (1+1)-dimensional soliton, which vortex solitons will be found in (2+1)-dimensional soliton transmission. In addition, numerical investigation of the (1+1)-dimensional spatial solitons interaction shows that the phenomenon of fusion and splitting during transmission is influenced by another beam and adjacent waveguides.