A novel design of highly nonlinear golden spiral Ge-doped core photonic crystal fiber for supercontinum light sources application

This paper presents a design of an Index-guiding Fiber using air holes arranged in Golden spiral lattice and a higher refractive index Germania (GeO₂) core (GGS-PCF), with all normal group velocity dispersion (GVD) and high nonlinear coefficient to generate light sources based on Supercontinum Generation. By placing a Ge-rod inside, near the center of the core, we increase the nonlinear coefficient to 108 W^-1km^-1 at 1.55μm. In Simulation, we used Finite Element Method (FEM) with a circular Perfect Matched Layer boundary (PML) to calculate the electric field and modal effective index. Then the process of solving nonlinear Schrodinger equation was studied to obtain spectrum property after propagating picosecond sech² pulses through 80m of fiber length. And the result has shown that this GGS-PCF can be usefully exploited in light source applications.