US 12,422,622 B2
Photonic systems comprising an asymmetric coupler and methods of fabrication
Justin Colby Norman, Goleta, CA (US); Michael Davenport, Santa Barbara, CA (US); and Michael Lawrence Belt, Goleta, CA (US)
Assigned to Quintessent Inc., Goleta, CA (US)
Filed by Quintessent Inc., Goleta, CA (US)
Filed on Dec. 1, 2022, as Appl. No. 18/073,226.
Claims priority of provisional application 63/285,011, filed on Dec. 1, 2021.
Prior Publication US 2023/0168431 A1, Jun. 1, 2023
Int. Cl. G02B 6/293 (2006.01); G02F 1/025 (2006.01); G02F 1/225 (2006.01); G02B 6/12 (2006.01)
CPC G02B 6/29338 (2013.01) [G02F 1/025 (2013.01); G02F 1/225 (2013.01); G02B 2006/12097 (2013.01); G02F 2201/063 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A photonic element comprising a ring resonator that includes:
a ring waveguide having a first ridge and a first slab having an inner ring-slab portion and an outer ring-slab portion; and
a bus waveguide having a second ridge and a second slab having an inner bus-slab portion that is proximal to the first ridge and an outer bus-slab portion that is distal to the first ridge;
wherein the ring waveguide and bus waveguide collectively define an asymmetrical single-polarization coupler having a coupling region, and wherein, within at least a portion of the coupling region:
(i) the outer ring-slab portion and the inner bus-slab portion are the same slab portion; and
(ii) the inner bus-slab portion has a first dimension and the outer bus-slab portion has a second dimension that is smaller than the first dimension, wherein the first dimension and second dimension are the same dimension and are selected from the group consisting of width and thickness; and (iii) the outer bus slab portion is configured to enable beta-matching between the bus waveguide and the ring waveguide.