Abstract

If light diffracting through a photosensitive material increases the refractive index significantly, the diffraction of the beam can be overcome and a self-written waveguide starts to form.¹’² We report on the first observations of photosensitivity in potassium ion-exchanged Nd-doped (1.5- wt%) Bk7 borosilicate glass, and create self-written waveguides in this material. Gratings have previously been written in a similar material (ion-exchanged silica) where index changes in the order of 10⁻⁵ were reported.⁴

© 2002 Optical Society of America