Title :
Photonic Crystal Fiber With Two Infiltrated Air Holes for Temperature Sensing With Excellent Temporal Stability
Author :
Yang, Minwei ; Wang, D.N.
Author_Institution :
Dept. of Electr. Eng., Hong Kong Polytech. Univ., Kowloon, China
Abstract :
A photonic crystal fiber sensor is created by infiltrating liquid with higher refractive index than background silica into two adjacent air holes situated in different layers. When the refractive index of the liquid is decreased to that of silica by heating, the two liquid rods and the solid core form a three-parallel-waveguide structure, which enables efficient mode energy coupling between the two eigenmodes and results in an interference fringe pattern. Theoretical analysis has been carried out to reveal the modes involved in the interference. Moreover, the temporal stability of the device is enhanced by inserting short sections of ultraviolet curable glue at both ends of the liquid, followed by solidification, to prevent the liquid-air interface fluctuation. The temperature sensitivity achieved is ~ -8.8 nm/°C, in the range between 45 and 50°C.
Keywords :
fibre optic sensors; holey fibres; light interference; refractive index; temperature sensors; infiltrated air holes; interference fringe pattern; liquid rods; liquid-air interface fluctuation; mode energy coupling; photonic crystal fiber sensor; refractive index; solid core; temperature 45 degC to 50 degC; temperature sensing; temperature sensitivity; temporal stability; three parallel waveguide structure; ultraviolet curable glue; Couplings; Interference; Liquid waveguides; Liquids; Silicon compounds; Thermal stability; Femtosecond (fs) laser ablation; optical fiber interferometer; optical fiber sensors; photonic crystal fiber (PCF);
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2012.2220121
