Optical coupler having exposed subwavelength gratings for coupling electromagnetic field

An assembly comprising:

• a semiconductor photonic device having:
• a substrate;
• a plurality of facets;
• and
• a plurality of optical couplers associated with respective facets of the plurality of facets;
• and
• a plurality of single-mode optical fibers disposed in a splice configuration with respect to respective facets of the plurality of facets;
• wherein each optical coupler of the plurality of optical couplers comprises:
• a respective first waveguide spaced apart from the respective facet of the plurality of facets;
• and
• means for coupling an electromagnetic field incident on the respective facet towards the respective first waveguide as the electromagnetic field proceeds into the semiconductor photonic device.

An assembly, wherein:

• the assembly comprises a semiconductor photonic device having:
• a plurality of facets;
• and
• a plurality of optical couplers associated with respective facets of the plurality of facets;
• each optical coupler of the plurality of optical couplers comprises:
• a respective first waveguide;
• a respective second waveguide spaced apart from the respective facet;
• and
• a respective third waveguide;
• and
• in each optical coupler:
• the respective first waveguide, the respective second waveguide, and the respective third waveguide are spaced apart in a lateral direction of that optical coupler;
• and
• at least one of the respective first waveguide, the respective second waveguide, and the respective third waveguide comprises a plurality of segments spaced apart in a longitudinal direction of that optical coupler.