Design and optimization of index guiding photonic crystal fiber-based gas sensor

Abstract

Hydrogen sulfide(H2S) and methane(CH4) are flammable, toxic, and colorless gases that exist in oil rigs/refineries. The PCF based gas sensors can detect the concentration of chemical materials such as hydrogen sulfide and methane. This paper presents a hexagonal PCF for sensing these gases. Characteristics of the proposed structure have been investigated for the wavelength range of 1.1 μm–1.6 μm using the full vector finite element method (FEM). The numerical results show that using non-circular holes around the central ring holes and a higher number of ring holes improves sensitivity and confinement loss respectively. Eventually, the relative sensitivity is enhanced to 62.07% and 67.07% and also the confinement loss 2.33 × 10−9dB/m and 8.61 × 10−5dB/m at the wavelength of 1.33 μm and λ = 1.578 μm at which the CH4 and H2S have a strong absorption line, respectively.