Supermode filtering waveguide emitters

A method of fabricating a supermode filtering waveguide (SFW) emitter, the method comprising:

• forming a first cladding layer over a semiconductor substrate;
• forming a first optical waveguide above the first cladding layer;
• forming a spacer layer above the first optical waveguide;
• forming a second optical waveguide above the spacer layer, wherein the second optical waveguide is configured, in conjunction with the first optical waveguide, to selectively propagate only a first mode of a plurality of optical modes;
• forming an optically active region in one of the first optical waveguide and the second optical waveguide;
• and
• forming a second cladding layer over the second optical waveguide.

An optical system comprising:

• a photonic chip comprising an optical component having a predefined height relative to a first surface of the photonic chip;
• a semiconductor substrate having a second surface;
• and
• a supermode filtering waveguide (SFW) emitter contacting the second surface, the SFW emitter comprising:
• a first optical waveguide;
• a spacer layer;
• a second optical waveguide spaced apart from the first optical waveguide by the spacer layer, wherein the second optical waveguide is evanescently coupled with the first optical waveguide and configured, in conjunction with the first waveguide, to selectively propagate only a first mode of a plurality of optical modes;
• and
• an optically active region disposed in one of the first optical waveguide and the second optical waveguide,
• wherein, when the second surface contacts the first surface, one of the first optical waveguide and the second optical waveguide is optically aligned with the optical component in at least one dimension.