Design of uncomplicated triangular core PCF for enhanced non-linearity applications

Abstract

An innovative design of Photonic Crystal Fibre (PCF) for enhanced non-linearity applications using simulation with the Finite Element Method (FEM) is presented. The PCF is a kind of fibre optic waveguide that has air-holes along the entire length of the optical fibre, which exploits its exclusive features of being continuously single-moded and having a modifiable spot-size and dispersion properties for various linear and non-linear applications. This proposed triangular core PCF is made of silica material with a refractive index of 1.445 and features three large air-holes placed 120° apart in the core, each with a refractive index of 1.00. The air-holes have a pitch length of 6.03 μm and a radius of 2.86 μm, and the wavelength of operation is 1.55 μm. The proposed PCF design has a large diameter to pitch ratio (d/Λ) of up to 0.95, resulting in a reduced spot-size of just above 1.00 μm2. This indicates that the proposed triangular core PCF design could be used to enhance non-linearity applications. This study introduces a novel structure that simplifies construction by employing three strategically positioned large air-holes in the cladding, thus achieving the necessary properties for guiding light through the core. This streamlined approach overcomes complexities associated with previous designs from the literature, hence, offering a practical solution for effective light guidance while minimising construction difficulties. This inventive proposed PCF design can be fabricated using the Stack and Draw process or the slurry casting method.