High-precision alcohol sensing using twin core photonic crystal fiber

Abstract

A novel twin-core photonic crystal fiber (TC-PCF) sensor for alcohol detection has been introduced that specifically targets ethanol, propanol, butanol and pentanol. The sensor utilizes silica as a substrate material with circular air holes in the cladding region and operates between 2 µm and 3 µm range of wavelength. Simulations and evaluations are performed on COMSOL Multiphysics software interface. The twin core structure of this sensor contributes to its enhanced or high-precision sensitivity, and the TC-PCF is versatile, making it suitable for detecting four different types of alcohol. This sensor reveals exceptional wavelength sensitivities of 8383.168 nm/RIU, 13759.69 nm/RIU and 14554.26 nm/RIU for ethanol, propanol and butanol respectively for the fiber length of 1600 µm. The amplitude sensitivity for ethanol, propanol, and butanol are 2.95 RIU⁻¹, 5.16 RIU⁻¹ and 5.82 RIU⁻¹ respectively, while the corresponding resolutions for ethanol, propanol and butanol are 119.2 × 10⁻⁷ RIU, 72.6 × 10⁻⁷ RIU and 68.7 × 10⁻⁷ RIU respectively. The figures of merit (FOM) are 29.50 RIU⁻¹, 46.19 RIU⁻¹ and 53.26 RIU⁻¹ for ethanol, propanol and butanol respectively. The sensor offers high sensitivity, a compact design and ease of fabrication which offers significant advantages over traditional alcohol detection methods, making it highly suitable for future alcohol sensing applications.