Sensitivity and Confinement Loss Analysis of a Porous-core Decagonal Photonic Crystal Fiber (P-DPCF) Based Chemical Sensor

A porous-core decagonal photonic crystal fiber (P-DPCF) has been developed for use in chemical sensing in this work. The core region has a hexagonal structure with three layers of circular air holes, while the cladding is decagonal and features five concentric rings of circular air holes. A full-vectorial finite element method (FEM) is applied to perform the numerical analysis. This work observes that increasing the air-filling ratio and core radius results in higher sensitivity while simultaneously reducing the confinement loss. Additionally, reducing the core pitch leads to enhanced sensitivity and a mitigate in confinement loss. Furthermore, the effective mode area for the fundamental modes along the X and Y directions is evaluated by varying the core radius and pitch. This work is designed a PCF-based platform for chemical sensing applications, specifically for benzene detection, and the performance results are presented for benzene (n = 1.366). Here, the operating wavelength spans from 1.30 µm to 1.75 µm. At 1.55 µm operating wavelength, the fiber determines a larger relative sensitivity of around 81.55% and an extremely lower confinement loss of about 2.8994 × 10⁻11dB/m.