A comparative analysis of two different PCF structures for gas sensing application

Toxic or Flammable gases and leakage of the gas lines can be detected by photonic crystal fibers for avoiding pollution, explosion or fire. Two different structures of hollow core based Photonic crystal fiber (HC-PCF) has been presented in this paper. The sensitivity of the proposed structures was numerically investigated by finite element method (FEM) varying the optical and geometrical properties. The numerical results show that the proposed PCF with six air holes shows 2.22 times higher sensitivity than the PCF with eight air holes in the first layer. Both of the PCFs exhibit reduced confinement loss also. The proposed PCFs can sense the lower refractive index based gases (toxic/ flammable) at a wide range of wavelength 0.8 µm to 2µm.