Three-hole microstructured optical fiber for efficient fiber Bragg grating refractometer.
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.
Phan Huy
Minh Châu
MC
Comissariat à l'Energie Atomique LIST, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette Cedex, France.
Laffont
Guillaume
G
Dewynter
Véronique
V
Ferdinand
Pierre
P
Roy
Philippe
P
Auguste
Jean-Louis
JL
Pagnoux
Dominique
D
Blanc
Wilfried
W
Dussardier
Bernard
B