We introduce a family of slot photonic crystal waveguides(SPh CWs) for the hybrid integration of low-index active materials in silicon photonics with energy-confinement factors of ~30% in low-index regions. The propos...We introduce a family of slot photonic crystal waveguides(SPh CWs) for the hybrid integration of low-index active materials in silicon photonics with energy-confinement factors of ~30% in low-index regions. The proposed approach, which is based on a periodic indentation of the etched slot in the middle of the SPh CW, makes it possible to reconcile a simultaneously narrow and wide slot for exploiting the two modes of even symmetry of a SPh CW. The resulting mode-selection mechanism allows a flexible choice of the modes to be used. Furthermore,the proposed structure offers tremendous flexibility for adjusting the dispersive properties of the slot-confined modes, in particular of their slow-light effects. Flat band slow light in a bandwidth of about 60 nm with a group velocity dispersion factor jβ_2 j below 1 ps^2∕mm is numerically demonstrated by this approach, corresponding to a normalized delay bandwidth product of around 0.4. These results, obtained from hollow-core periodic waveguides that are directly designed in view of hybrid integration of active materials in mechanically robust structures(not based on free-standing membranes) could pave the way for the realization of on-chip slow-light bio-sensing,active hybrid-silicon optoelectronic devices, or all-optical hybrid-silicon nonlinear functionalities.展开更多
文摘We introduce a family of slot photonic crystal waveguides(SPh CWs) for the hybrid integration of low-index active materials in silicon photonics with energy-confinement factors of ~30% in low-index regions. The proposed approach, which is based on a periodic indentation of the etched slot in the middle of the SPh CW, makes it possible to reconcile a simultaneously narrow and wide slot for exploiting the two modes of even symmetry of a SPh CW. The resulting mode-selection mechanism allows a flexible choice of the modes to be used. Furthermore,the proposed structure offers tremendous flexibility for adjusting the dispersive properties of the slot-confined modes, in particular of their slow-light effects. Flat band slow light in a bandwidth of about 60 nm with a group velocity dispersion factor jβ_2 j below 1 ps^2∕mm is numerically demonstrated by this approach, corresponding to a normalized delay bandwidth product of around 0.4. These results, obtained from hollow-core periodic waveguides that are directly designed in view of hybrid integration of active materials in mechanically robust structures(not based on free-standing membranes) could pave the way for the realization of on-chip slow-light bio-sensing,active hybrid-silicon optoelectronic devices, or all-optical hybrid-silicon nonlinear functionalities.