Design of waveguides in silicon phoxonic crystal slabs
Résumé
We consider the problem of designing waveguides in nanostructures presenting simultaneously phononic and photonic band gaps. We specifically opt for designs in perforated silicon membranes that can be conveniently obtained using silicon-on- insulator technology. Geometrical parameters for simultaneous photonic and phononic band gaps are first chosen, based on the finite element analysis of a perfect phoxonic crystal of circular holes. A plain core waveguide is then defined, and simultaneous slow light and elastic guided modes are identified. Joint confinement of light and elastic waves with group velocities reduced by a factor of a few tens is predicted.