The integration of magneto-optical materials to realize non-reciprocal functions is still a difficult problem, because
classical magneto-optical materials require an annealing temperature as high as 700°C. In this framework, this study
shows how it is possible to realize efficient magneto-optical mode converter using the association of a magnetic
nanoparticles silica/zirconia composite with an ion-exchanged glass waveguide.
Using a sol gel process, a silica/zirconia matrix is doped by magnetic nanoparticles (CoFe2O4) and coated on a glass
substrate containing straight channel waveguides made by a silver/sodium ion exchange. The extremities of the guides
were previously buried using electric field-assisted burial in order to facilitate light injection. Soft annealing (90°C) and
UV treatment, both compatible with the ion exchange process, have been implemented to finalize the magneto-optical
film.
Depending on the amount of nanoparticles in the composite, on the spatial distribution of the field in the guide and on the
modal birefringence of the hybrid structure, the TE-TM conversion varies from several degrees to several tens of
degrees.
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