Study On Special Physical Phenomena Of Compound Periodic Optic Lattices

Photonic lattice,a mesoscopic artificial structure,which contributes to optic and quantum field.The study of photonic lattice has always been a hot topic in the field of optics.Classical photonic lattices,such as triangular lattice,square lattice,Honeycomb lattice,Kagome lattice and Lieb lattice.Duo to the different periodic arrangement of lattices,the natures of the band structure are different,which will show many different optical properties.For instance,Kagome and Lieb lattice who have the flat band structure can realize optical local transmission under linear conditions duo to the flat band dispersion.And recently Song Daohong and Chen Zhigang et al.unveil pseudospin and angular momentum in photonic graphene because the Dirac pints of special band structure show the double degenerate.For this reason,the idea about studying on new type of complex periodic photonic lattices is raised.In this paper,we mainly study the contents as follow: Based on the theory of quasi non-diffracting,we design new two-dimensional compound lattices and three-dimensional lattices by making the superposition of two lattices whose size and the angle of rotation are different respectively.According to the different types of lattice,we do some researches on vortex structure,band structure,transmission and the pseudospin.The main work is as follows:1.First,based on the Bessel beam,we take several symmetric points on the two concentric rings as the point source,and make the new three dimensional compound periodic lattices through Fourier transform.2.We also study the standard lattice superposition,produce two kinds of two-dimensional complex new quasi non-diffracting lattices,octagon and dodecagon lattices.The new lattices are in good periodicity and can keep no-diffraction in a long propagation distance and we use Plane Wave Expansion Method to calculated the band structure of similar optic crystal.3.Based on nonlinear Schrodinger equation and the Step Fourier algorithm,we simulate the light transmission in octagon and dodecagon lattices under the linear and nonlinear conditions,the light can realize the localization in nonlinear condition,and we discover theexistence of pseudospin in the two compound lattices.After that,we carried out the experimental verification.