High intensity ArF laser irradiation produces Bragg gratings with index modulations >10-3 in standard germanium-doped silica waveguides without hydrogen loading. A UV-induced birefringence of 2×10-4 is used to compensate for the inherent birefringence of the silica waveguides and makes the grating response identical for TE and TM modes.

Electronics Letters
Department of Electronics

Albert, J, Bilodeau, F., Johnson, D.C., Hill, K.O., Mihailov, S.J., Stryckman, D., … Hibino, Y. (1998). Polarisation-independent strong Bragg gratings in planar lightwave circuits. Electronics Letters. doi:10.1049/el:19980338