Phosphate glasses containing enough sodium to allow the fabrication of optical channel waveguides by ion exchange are photosensitive to intense ultraviolet irradiation from excimer lasers at 193 and 248nm. Permanent submicrometer-period volume index gratings with modulation amplitudes larger than 10<sup>−4</sup> were obtained even after annealing the irradiated samples for 2h at 230°C. Ultraviolet-visible absorption changes were measured in the irradiated areas, as well as structural modifications observed by surface profiling. Comparative studies were carried out for glasses that were also codoped with erbium and ytterbium to provide high gain at wavelengths near 1.5μm. Finally, we demonstrate narrowband gratings with reflectivities larger than 80% in silver ion-exchanged channel waveguides made in these phosphate glass substrates.
© 2006 Optical Society of America
Diffraction and Gratings
Original Manuscript: May 12, 2006
Revised Manuscript: August 7, 2006
Manuscript Accepted: August 29, 2006
Sanna Yliniemi, Seppo Honkanen, Anatoli Ianoul, Albane Laronche, and Jacques Albert, "Photosensitivity and volume gratings in phosphate glasses for rare-earth-doped ion-exchanged optical waveguide lasers," J. Opt. Soc. Am. B 23, 2470-2478 (2006)