Defect population in silica glasses studied by luminescence VUV excitation spectroscopy
Résumé
Defect population in germania-silica optical fibre preform is studied. Seven excitation bands are pointed out in the range 100–300 nm. They are associated with seven different defects. Two of them are new, two others are currently observed in absorption but are never mentioned as giving rise to a luminescence. We show that 248 nm laser irradiation bleaches the defects having an excitation band wavelength close to one of the lasers, whereas the others are unchanged or enhanced.