Dye-doped zirconia-based Ormosil planar waveguides: Optical properties and surface morphology

Zirconia-based Ormosil planar waveguides with different ZrO2 contents were produced by a low temperature sol-gel process and subsequent spin coating on microscope glass slides. Propagation losses as low as 0.5 dB/cm or less were found at 488 nm for films with low ZrO2 content; in contrast, worse waveguide quality was observed with increasing ZrO2 doping level. A morphological investigation by atomic force microscopy confirmed such result, giving evidence of an increase of surface roughness with ZrO2 percentage. The feasibility of organic dye doping of the films for active waveguides was also demonstrated by incorporation of DODCI saturable absorber: fluorescence spectra were registered both in bulk and guided-wave configuration.