Guiding Properties of the Ge-Based Square Lattice Photonic Crystal Fibers

Abstract

The dispersion properties of the Ge composed square lattice photonic crystal fibers (PCFs) are thoroughly analyzed for the first time. The influences of air hole size and hole-to-hole spacing on dispersion are also reported. For the smallest air filling fraction 0.1, flattened dispersion D(λ) of 6 ps/km-nm was obtained from 1200 nm to 1600 nm, spreading over 400 nm wide wavelength range. As a multimode fiber, the mode profiles of the fundamental and second order modes are clearly presented. They are strongly localized in the core and guided through the photonic crystal fiber. This fiber with flattened dispersion is more appropriate than silica PCFs and a good candidate for using in optoelectronic components, optical telecommunications, WDM optical fiber transmission system successfully.