Broadband, group index independent, and ultra-low loss coupling into slow light slotted photonic crystal waveguides

摘要

The present invention provides a waveguide coupler configured to optically couple a strip waveguide to a first slot photonic crystal waveguide, wherein the slot photonic crystal waveguide has a lattice constant, an air hole diameter, a slot width and a first line defect waveguide width. The waveguide coupler includes a group reflective index taper having a second slot photonic crystal waveguide disposed between and aligned with the first slot photonic crystal waveguide and the strip waveguide. The second slot photonic crystal waveguide has a length, the lattice constant, the air hole diameter, the slot width, and a second line defect waveguide width that is substantially equal to the first line defect waveguide width adjacent to the first slot photonic crystal waveguide and decreases along the length of the second photonic crystal waveguide.

主权项

1. An optical apparatus comprising a waveguide coupler configured to optically couple a strip waveguide to a first slot photonic crystal waveguide, wherein the slot photonic crystal waveguide has a lattice constant, an air hole diameter, a slot width and a first line defect waveguide width, wherein the waveguide coupler comprises:
a group reflective index taper comprising a second slot photonic crystal waveguide disposed between and aligned with the first slot photonic crystal waveguide and the strip waveguide, wherein the second slot photonic crystal waveguide has a length, the lattice constant, the air hole diameter, the slot width, and a second line defect waveguide width that is substantially equal to the first line defect waveguide width adjacent to the first slot photonic crystal waveguide and the second line defect waveguide width increases along the length of the second photonic crystal waveguide from the strip waveguide to the first slot photonic crystal waveguide.