Solid Core Holey Photonic Crystal Fiber for High Optical Confinement & Tailored Dispersion

Abstract

Conventional optical fibers can only guide light in a high refractive index core by total internal reflection. By using total internal reflections, it is not possible to guide light in an air core. Light guidance in air is of great interest for various technological and scientific applications and has only recently been possible with the advent of photonic band gap fibers. Control of dispersion in PCFs is very important problem for realistic applications of optical fiber communications, dispersion compensation and nonlinear optics. Usually the positive dispersion of the optical fiber, which is a major factor to cause optical pulse broadening and restrict transmission distance and bandwidth, can be compensated by using dispersion compensating fiber (DCF) with large negative dispersion. The present work aims at the designing and simulation of a structure with high electric field distribution, low group velocity and low group velocity dispersion single mode photonic crystal fibers. By varying various parameters such as radius of air holes (r), number of air holes rings (N), dielectric constant of material (ε), and lattice constant (a) analysis has been done for an optimum profile. In ε=12, provides maximum electric field distribution and low group velocity dispersion in the largest possible wavelength window, in which the dispersion varies from -0.3420 to –1.1324 ps/nm/km, providing a group velocity 0.19c. For ε=7.84, flattened group velocity dispersion in a range of -0.2688 to -0.3536 ps/nm/km and group velocity 0.22c have been achieved. Largest negative group velocity dispersion ranging from - 0.9875 to -0.5376 ps/nm/km has been achieved with ε=2.1, for which group velocity touched the value of 0.38c within the minimum wavelength window of 0.59 to 1.00μm.