Design and analysis of porous core photonic crystal fiber based ethylene glycol sensor operated at infrared wavelengths

Abstract

A novel porous core photonic crystal fiber (PCF) sensor is reported for label-free detection of different concentrations of ethylene glycol present in aqueous solution, over a wavelength range from 1 to 2 μm. Both core and cladding are designed with elliptical air holes, which are arranged in a hexagonal structure with TOPAS as the background material. Various geometrical parameters are judiciously optimized to achieve an efficient sensor. Finite element analysis is employed for numerical simulation of the proposed structure, investigating various sensing parameters including effective refractive index, effective material loss, confinement loss, nonlinearity coefficient, shifts in peak reflected wavelengths, sensitivity, f-parameter, spot size and beam divergence angle. Simulation outcomes reveal a significant shift in the sensing parameters in response to changes in concentration of ethylene glycol, confirming the effectiveness of the sensor. Optimum wavelength sensitivity of 13,144.86 nm/RIU and resolution of $$7.46 \times 10^{ - 7}$$ RIU are attained, which provide a significant theoretical foundation for the design of novel photonic sensors. Benchmarking of the proposed PCF sensor is done against related research results to prove its superiority in terms of resolution and sensitivity.