Thermal reliability of Bragg gratings written in hydrogen-sensitized fibers

Summary form only given. In this work, the thermal reliability of gratings in hydrogen-loaded fibers is studied. It is known that the refractive index modulation in the fiber core is caused by UV-generated defects in the fiber core. It may, hence, be expected that a thermally induced decrease in concentration of the defects that are responsible for the refractive index change would also reduce the UV-induced index modulation, which in turn would decrease the spectral width in strong gratings.