Title :
Ultra Sensitive Fiber-Optic Hydrogen Sensor Based on High Order Cladding Mode
Author :
Kim, Young Ho ; Kim, Myoung Jin ; Rho, Byung Sup ; Park, Min-Su ; Jang, Jae-Hyung ; Lee, Byeong Ha
Author_Institution :
Gwangju Inst. of Sci. & Technol., Gwangju, South Korea
fDate :
6/1/2011 12:00:00 AM
Abstract :
We demonstrate a simple but sensitive hydrogen gas sensor composed of a palladium-coated long-period fiber grating (LPG). By writing an LPG in a low core index fiber, high-order cladding modes are excited. As the palladium thin layer absorbs hydrogen, the effective refractive indexes of the cladding modes are affected, thus the resonant wavelengths of the LPG are changed with a high sensitivity. With 70-nm-thick coating, 7.5 nm of the hydrogen-induced spectral shift was achieved. The spectral response of the proposed sensor to hydrogen gas and its recovery with nitrogen gas are presented.
Keywords :
fibre optic sensors; gas sensors; optical fibre cladding; palladium; refractive index; spectral line shift; LPG; high-order cladding mode; hydrogen-induced spectral shift; palladium thin layer; palladium-coated long-period fiber grating; refractive index; sensitive hydrogen gas sensor; size 7.5 nm; size 70 nm; spectral response; ultrasensitive fiber-optic hydrogen sensor; Coatings; Indexes; Optical fiber communication; Optical fiber sensors; Palladium; Fiber optic device; fiber sensor; hydrogen sensor; long-period fiber grating;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2010.2092423
