The Design And Analysis On Two Zero-Dispersion Of Photonic Crystal Fibers

The dispersion and nonlinearity of photonic crystal fibers are two important fields investigated in supercontinuum. Two zero-dispersion of photonic crystal fibers is an important choice in studying nonlinearity. The two zero-dispersion properties, nonlinearity properties, confinement loss properties of index guiding photonic crystal fibers are investigated theoretically in this paper. Some photonic crystal fibers have been designed, The main results are summarized as follows:First, based on Multi-Pole Method (MPM), two zero-dispersion properties, dispersion slope, nonlinear coefficient and confinement loss of photonic crystal fibers with hexagonal structure as a function of wavelength is investigated from the wavelength of 0.8 to 1.8μm .We analyze and compare the dispersion coefficient, dispersion slope, nonlinear coefficient, confinement loss of the same structure parameters with hexagonal structure, octagonal structure and decagonal structure. The photonic crystal fiber with hexagonal structure is more fit for dispersion compensation and high non-linear studies. The dispersion of photonic crystal fiber with decagonal structure is much flatter, the confinement loss of decagonal structure is much lower, the cladding structure of photonic crystal fibers closer to the circular structure, the dispersion of which is much flatter, the nonlinear coefficient and the confinement loss of which are much lower.Second, an new structure of photonic crystal fibers with low confinement loss and flatted dispersion is designed. The influence of structure parameters on dispersion and confinement loss of photonic crystal fibers are analyzed. A PCF with flattened dispersion and low confinement loss is obtained. The dispersion is less than 0.58 ps/km/nm and is larger than -0.11 ps/km/nm from 1.31μm to 1.6μm .The confinement loss is 0.16 dB/km at 1.55μm.The final, the nonlinear properties of photonic crystal fiber are investigated, the two ways to enhance the nonlinear coefficient are introduced. A simple double cladding structure of broadband two-zero dispersion and highly nonlinear photonic crystal fiber is designed, the influence of double cladding structure parameters on two zero-dispersion, dispersion slope and nonlinear properties of photonic crystal fibers are analyzed. A flatted dispersion and highly nonlinear photonic crystal fiber with simple hexagonal structure is designed, and the nonlinearity of highly nonlinear photonic crystal fiber is tested.