Photosensitivity of ion-exchanged Er-doped phosphate glass using 248nm excimer laser radiation

The photosensitivity to 248nm excimer laser radiation of Er-doped Schott IOG-1 phosphate glass is presented. The photosensitive mechanism is investigated by employing a grating recording process. Index changes of up to similar to 2.0 x 10(-3) were measured in silver ion-exchanged samples using diffraction efficiency measurements; whereas changes of only similar to 10(-5) were measured for non-ion-exchanged samples. Absorption measurements allowed the identification of specific color center bands, which were attributed to the glass matrix and to the silver ions. Investigation of the exposed ion-exchanged glass using scanning electron microscopy and energy dispersive x-ray microanalysis revealed that in addition to the color centers formed, silver ion migration and ionization contribute significantly to the UV-induced index changes. (C) 2004 Optical Society of America.