Thinned fiber Bragg gratings as high sensitivity refractive index sensor

In this work, the numerical and experimental analysis on the use of thinned fiber Bragg gratings as refractive index sensors have been carried out. Wet chemical etching in a buffered hydrofluoric acid solution was used for sensor fabrication. Experimental characterization for an almost full etched cladding sensor is presented demonstrating good agreement with numerical results and resolutions of ≈10^-5 and ≈10^-4 for outer refractive index around 1.45 and 1.333, respectively.