Phase matching for efficient nonlinear frequency generation in hybrid Si/chalcogenide glass slot waveguides

We present a novel design route for Silicon/chalcogenide hybrid slot waveguides, which allows waveguide geometries with FOM > 1 and a maximum field concentration within the infiltrated material and a vanishing group velocity dispersion (GVD) at the same time. The independent adjustment of the GVD and the mode profile is achieved by a small periodic variation of the refractive index along the waveguide. This introduces a photonic band gap for the waveguide mode leading to additional band bending in the vicinity of this band gap.