The Fabrication And Propagation Properties Of The Colloidal Crystal Cladding Micro-fiber

Colloidal crystal microstructure fiber is a new type of waveguide materials and an amalgam of colloid crystals and optical fiber. Compared to the single mode optical fiber and photonic crystal fiber, the colloidal crystal microstructure fiber has many terrific advantages. It has attracted huge attention of the researchers. Rely on its’ simple production process, low cost and other characteristics, colloidal crystal microstructure fiber can be widely used in optical filters, fiber sensor and optical devices.This thesis contains theoretical analysis and experimental research, such as the calculation of the photonic band gap, the fabrication of colloidal crystal on the micro fiber, surface characterization of the colloidal crystals by SEM image and spectral characteristics of colloidal photonic crystals fiber. the main work of this thesis includes:1.Simulative calculation of photonic band gap center wavelength: We calculated photonic band gap center wavelength of microspheres with different diameters by using Bragg reflection method and plane wave expansion method respectively, which theoretically proved the feasibility of our experiment. First of all, we utilized the modified optical Bragg reflection formula to calculate preliminarily the photonic band gap wavelength of polystyrene spheres with different diameters to sort out the proper microsphere for the experiment later. Then, we established a seven-layer model of colloid crystals by use of the module Bandsolve of Rsoft Photonics Suite CAD software. Taking advantage of the plane wave expansion method, we obtained the photonic band gap wavelength corresponding to the two kinds of polystyrene microspheres with diameters of 619.7nm and 300 nm, which offered some reference when we selected the type of spectrometer in the subsequent experiment.2. The formation of microstructure optical fiber was introduced in detail and the two kinds of polystyrene spheres with diameters of 619.7 nm and 300 nm were used to fabricate colloidal crystals on the surface of the micro-structure optical fiber. The growth-experiment of colloidal crystal on surface of the optical fiber proved that both of surface hydrophilicity of microstructure optical fibers and the distribution of microsphere size would affect the self-assembly of colloidal crystal.3. Analysis of the features of the colloidal photonic crystal fibers: different detective range of spectrometer were used respectively to investigate the characterization of the transmission spectrum of colloidal crystal microstructure fibers fabricated by polystyrene microspheres with the diameters of 619.7 nm and 300 nm. The experimental results validate the theoretical simulation very well. Scanning electron microscopy(SEM) was also used to observe the morphology of the colloidal crystals which were fabricated respectively by polystyrene microspheres with the diameters of 619.7 nm and 300 nm. The SEM results demonstrated that colloidal crystal was constructed by face-centered cubic cells(FCC) which array as a multilayer structure.