| 摘要 |
A slab of a rib waveguide includes geometric disruption features along a direction of propagation of the waveguide. The geometric disruption features scatter optical modes other than the fundamental mode in the slab without significantly impacting the fundamental optical mode that propagates primarily in the rib waveguide. The rib waveguide has a width to constrain the fundamental mode, and the fundamental mode primarily propagates through the rib waveguide, with some of the energy propagated via the slab. When the slab includes edges that are wider than the rib waveguide and smaller than the substrate on which the rib waveguide and slab are integrated, the slab can propagate optical modes other than the fundamental mode, such as higher-order modes. The geometric disruptions scatter the non-fundamental optical modes from the slab. The geometric disruptions can include serration features in one or both edges of the slab. |
