title: Three-hole microstructured optical fiber for efficient fiber Bragg grating refractometer.
abstract: We present a photosensitive three-hole microstructured optical fiber specifically designed to improve the refractive index sensitivity of a standard fiber Bragg grating (FBG) sensor photowritten in the suspended Ge-doped silica core. We describe the specific photowriting procedure used to realize gratings in such a fiber. We then determine their spectral sensitivity to the refractive index changes of material filling the holes surrounding the core. The sensitivity is compared with that of standard FBGs photowritten in a six-hole fiber with a larger core diameter. We demonstrate an improvement in the sensitivity by two orders of magnitude and reach a resolution of 3 x 10(-5) and 6 x 10(-6) around mean refractive index values of 1.33 and 1.40, respectively.
authors: Comissariat à l'Energie Atomique LIST, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette Cedex, France.
authors: Minh Châu
authors: MC
authors: Phan Huy
authors: Guillaume
authors: G
authors: Laffont
authors: Véronique
authors: V
authors: Dewynter
authors: Pierre
authors: P
authors: Ferdinand
authors: Philippe
authors: P
authors: Roy
authors: Jean-Louis
authors: JL
authors: Auguste
authors: Dominique
authors: D
authors: Pagnoux
authors: Wilfried
authors: W
authors: Blanc
authors: Bernard
authors: B
authors: Dussardier