The Fabrication And Research Of Two- And Three- Dimensional Photorefractive Photonic Lattices

Photonic lattice is a kind of artificial structure with periodic dielectric coefficient,and it is a new type of optical materials. Two dimensional and three dimensionalphotonic lattices offer new possibilities to route, control, and steer light in all-opticalinformation processing and nanophotonic devices. Therefore, materials with periodicrefractive index modulations have become the subject of extensive research forseveral years now. The shortcomings of traditional fabrication methods of photoniclattices include process complexity, production difficulties, high costs, difficultlarge-scale production, etc. Optical induction method is a new method of makingphotonic lattices with advantages such as real-time, simple, low cost, and suitable forlarge-scale production. At present people have done a lot of research on onedimensional and two dimensional photonic lattices in photorefractive crystals, andhave found a lot of interesting phenomena, such as discrete spatio-temporal solitonsand quantum tunneling. Undoubtedly, three dimensional photonic lattices must havehaving more new nonlinear features and phenomena. However, the fabrication ofthree dimensional photorefractive photonic lattices remains a real challenge, as manyof the conventional methods become either technically unsuitable or extremelycomplicated.In this paper, the following several aspects works were doing:1. Briefly introduced the photonic crystals, Summarizes the development historyof nonlinear photonic lattices and its research status.2. Severa kinds of typical traditional fabrication methods of nonlinear photoniclattices being introduced in this paper. Mainly introduces the optical induction methodand photorefrective effect and the bandgap structure of photonic lattices.3. By improving the traditional Michelson interferometer and Fresnel biprism to achieve four beams interference and improve the light energy utilization of opticalpaths. Two-dimensional square photonic lattices can be induced in the10mm×5mm×10mm self-defocusing iron-doped lithium niobate photorefractivecrystal by optical induced method which has a large area （about 28mm²） and a longdark storage time. The period of two-dimensional photonic lattices can be controlledflexibly. This solves the weakness that only can get smaller effective area of photoniclattices by the traditional optical induced method, which is an innovative point in theresearch work of this paper. More research has been done to study the influence ofpolarization state of light irradiation, light intensity and irradiation time on opticalinduced photonic lattices.4. Three-dimensional hexagonal photonic lattices microstructure with a period of17μm has been constructed in self-defocusing LiNbO₃:Fe photorefractive crystal bysingle amplitude mask and Fourier transform lens for the first time. A kind ofinterferometer system used to produce large area three-dimensional photonic latticesis put forward. The system can realize wide-beam interference of multi-beam coherentlight and induced a large area of three dimensional hexagonal photonic lattices iniron-doped lithium niobate crystals. Induce three dimensional hexagonal photoniclattices microstructure in self-defocusing LiNbO₃:Fe crystals for the first time is themost important innovation of this paper. These work create the conditions for thefurther study of discrete diffraction and discrete solitons phenomenon in threedimensional photonic lattices, help us understand the method to manipulate lightwaves in mesoscale deeply and also promote the future development of newmesoscopic photonics devices.