Abstract
A novel pH sensor based on the deposition of electrostatic self-assembled polyallylamine hydrochloride and polyacrylic acid on the cladding of a long-period fiber grating has been designed. The overlay thickness is of the order of magnitude of the light wavelength used to interrogate the sensor. A theoretical model of multilayer cylindrical waveguides based on coupled-mode theory has been used to predict the position of the attenuation bands as a function of the overlay thickness. A study of the role that pH plays in the thickness of the sensitive overlay was carried out. Experimentally, a wavelength shift of the attenuation bands of up to was obtained in the 4–7 range of pH units. The results are reproducible, which indicates the possibilities of a multiple-use sensor.
© 2006 Optical Society of America
Full Article | PDF ArticleMore Like This
Ignacio Del Villar, Miguel Achaerandio, Ignacio R. Matías, and Francisco J. Arregui
Opt. Lett. 30(7) 720-722 (2005)
Ignacio Del Villar, Jesus M. Corres, Miguel Achaerandio, Francisco J. Arregui, and Ignacio R. Matias
Opt. Express 14(25) 11972-11981 (2006)
Bobo Gu, Ming-Jie Yin, A. Ping Zhang, Jin-Wen Qian, and Sailing He
Opt. Express 17(25) 22296-22302 (2009)