Organic-inorganic hybrid materials are a technologically key class of advanced multifunctional materials that fulfil the
challenging strict requirements of the beginning of the century: higher levels of sophistication, miniaturisation,
recyclability, reliability and low energy consumption with potential to be used as low-cost components in optical
networks operating at high bit rates. In this work, high-rejection optical filters (19 dB) first-order Bragg gratings
inscribed in channel waveguides written in thin films of sol-gel derived organic-inorganic hybrid based on methacrylic
acid modified zirconium tetrapropoxide, Zr(OPrn)4, (so-called di-ureasils), using UV-laser direct-write method.
In this work we report the systematic study of modal analysis in planar organic/inorganic sol-gel
waveguides with different compositions, thicknesses, incident wavelengths and substrates. Results
from two simulation methods and experimental data are presented and compared.