Bragg gratings in defect-free germanium-doped optical fibers

Bragg gratings have been written in germanium-doped optical fibers that hav e been treated to remove the UV absorption bands associated with oxygen-def icient defects. When one is using high-intensity 193-nm light from an ArF e xcimer laser to fabricate the gratings, the refractive index increases and the grating transmission spectra are similar to those obtained in standard (untreated) fiber. (C) 1999 Optical Society of America. OCIS codes: 060.234 0, 060.2290, 160.2750, 260.7190, 300.1030.