Fully compatible magneto-optical sol-gel material with glass waveguides technologies: application to mode converters

To overcome the difficult problem of the integration of magneto-optical materials with classical technologies, our group has developped a composite magneto-optical material made of a hybrid organic-inorganic silica type matrix doped by magnetic nanoparticles. Thin films of this material are obtained through a soft chemistry sol-gel process which gives a full compatibility with an integration on glass substarte. Due to an interesting magneto optical activity (Faraday rotation of 310°/cm) several magneto-optical functionnalities have been realized. A thin film of such composite material coated on a pyrex™ substrate acts as non-reciprocal TE/TM mode converter. An hybrid stucture made of a composite film coated on an ion-exchanged glass waveguide has been realized with a good propagation of light through a hybrid mode. Finally, the sol gel process has been adapted in order to obtain 3D inverse opals which should behave as magnetophotonic crystals. Transmittance curves reveal the photonic band gap of such opals doped with magnetic nanoparticles.