Research On Several Transmission Phenomena In Photonic Lattice

The photonic lattice system has many characteristics such as periodic refractive index and energy band gap.It can achieve the effects of adjustable parameters,controllable optical path and predictable transmission results for the propagation of light waves.It has great research value and application potential.Many physicists explore more novel and valuable optical phenomena by studying different light beams propagating in photonic lattices of different properties,laying the foundation for the development of photonic information technology.The transmission characteristics of light beams in defective photonic lattices and photonic topological insulators have been research hotspots in recent years.Both can produce some novel transmission phenomena by adjusting the lattice structure and parameters,such as non-diffracted beams,photorespirators,topological edge states and optical phenomena such as edge solitons.With the deepening of the research on the transmission characteristics of light in defective photonic lattices and photonic topological insulators,this paper proposes to study several transmission phenomena of photonic lattice systems,including non-local Topological states of photorespirators and photonic Floquet topological insulators in the nonlinear defect lattice in the domain.First,based on the finite difference method and the distributed Fourier transmission method,the propagation characteristics of two Airy-Gaussian beams in a one-dimensional non-local nonlinear defect lattice are discussed numerically.It is found that in most cases,the two Airy-Gaussian beams propagate in the non-local nonlinear defect lattice as quasirespirator morphology,but in the local nonlinear normal periodic lattice and the local nonlinear positive defect lattice Found the existence of tripolar solitons.In addition,non-local nonlinear parameters,lattice parameters and beam parameters will affect the morphology and period of quasi-respirators.Secondly,a photonic Floquet topological insulator model composed of oppositely spiraling honeycomb lattices is established,and the Zigzag-Zigzag(ZZ)domain wall and Zigzag-Zigzag(ZZ)domain wall Armchair-Armchair(AA)domain wall topological properties,and using the stepped Fourier transmission method to simulate the transmission process of structured light in the lattice,verify the existence of topological edge states at the domain wall,and find that the beam is on the domain wall The edge state strength of the transmission will be affected by the incident point of the beam in the Brillouin zone and the lattice spiral radius,and the beam will have opposite lateral velocities on the ZZ domain wall(AA domain wall)in the opposite direction.Although some novel transmission phenomena in the photonic lattice system have been discovered in this paper,there are still some research work to be carried out.For the study of the transmission of two Airy-Gaussian beams in a non-local nonlinear defect photonic lattice,only the one-dimensional situation is temporarily analyzed,but the research at the twodimensional level has not been involved;The research can also introduce other lattice structures,such as PT symmetry and disorder,etc.What is more important is that the research is only at the theoretical stage,and further verification needs to be completed through experiments later.