Cladding doped defect-core large mode area W-type photonic crystal fiber

Abstract

Propagation characteristics of a cladding doped defect-core large mode area W-type photonic crystal fiber have been investigated by using finite element method. In the proposed structure the central air hole has been removed to form the defect core and the second layer of cladding rings around the central core have been selectively doped with different concentration of fluorine to tune the refractive index of the doped silica rods. The bend loss, dispersion, effect of bending on dispersion, and nonlinear coefficient of the proposed photonic crystal fiber design has been numerically investigated. The proposed W-type photonic crystal fiber has low bend loss, low dispersion, large-mode-area with low value of nonlinear coefficient at wavelength of 1.55μm. The structure can be utilized for telecommunication applications, for applications in high power fiber lasers, amplifiers and sensors.