Photonic integrated circuit structure with polarization device for high power applications

Abstract

Disclosed is a structure including a polarization device with first and second waveguides. The first waveguide includes a core (e.g., a silicon nitride (SiN) core) suitable for high-power applications. The second waveguide includes: a primary core (e.g., another SiN core), which is positioned laterally adjacent to the core of the first waveguide and suitable for high-power applications, and secondary core(s) stacked vertically with the primary core to steer the optical mode and ensure that mode matching occurs between adjacent first and second coupling sections of the first and second waveguides, respectively, in order to achieve high-power splitter and/or combiner functions. Optionally, the primary and secondary cores of the second waveguide can be tapered at least within the second coupling section to increase the likelihood of mode matching.

What is claimed is: 
     
         1 . A structure comprising:
 a first waveguide with first end sections and a first coupling section between the first end sections, wherein the first waveguide comprises a first core; and   a second waveguide having second end sections and a second coupling section between the second end sections and adjacent to the first coupling section, wherein the second waveguide comprises:
 a second core positioned laterally adjacent to the first core; and 
 an additional second core stacked vertically with the second core. 
   
     
     
         2 . The structure of  claim 1 , wherein a first core material of the first core and a second core material of the second core both comprise silicon nitride. 
     
     
         3 . The structure of  claim 1 , wherein a first core material of the first core and a second core material of the second core comprise different nitride materials. 
     
     
         4 . The structure of  claim 1 , wherein a second core material of the second core and an additional second core material of the additional second core are a same core material. 
     
     
         5 . The structure of  claim 1 , wherein a second core material of the second core and an additional second core material of the additional second core are different core materials. 
     
     
         6 . The structure of  claim 1 , wherein a first sidewall of the first core in the first coupling section is parallel to a second sidewall of the second core in the second coupling section. 
     
     
         7 . The structure of  claim 1 , wherein a first sidewall of the first core in the first coupling section is angled relative to a second sidewall of the second core in the second coupling section. 
     
     
         8 . The structure of  claim 1 , wherein a first width of the first core in the first coupling section is essentially uniform and wherein a second width of the second core in the second coupling section is tapered. 
     
     
         9 . The structure of  claim 1 , wherein the second core and the additional second core are center-aligned and wherein, at least in the second coupling section, the second core has different dimensions than the additional second core. 
     
     
         10 . A structure comprising:
 a first waveguide with first end sections and a first coupling section between the first end sections, wherein the first waveguide comprises a first core; and   a second waveguide having second end sections and a second coupling section between the second end sections and adjacent to the first coupling section, wherein the second waveguide comprises:
 a second core positioned laterally adjacent to the first core; and 
 multiple additional second cores stacked vertically with the second core. 
   
     
     
         11 . The structure of  claim 10 , wherein the multiple additional second cores are stacked any of below the second core and above the second core. 
     
     
         12 . The structure of  claim 10 , wherein a first core material of the first core and a second core material of the second core are silicon nitride. 
     
     
         13 . The structure of  claim 10 , wherein a first core material of the first core and a second core material of the second core are different nitride materials. 
     
     
         14 . The structure of  claim 10 , wherein a second core material of the second core is different from additional second core materials of the multiple additional second cores. 
     
     
         15 . The structure of  claim 10 , wherein a second core material of the second core and an additional second core material of at least one of the multiple additional second cores are a same core material. 
     
     
         16 . The structure of  claim 10 , wherein a first sidewall of the first core in the first coupling section is parallel to a second sidewall of the second core in the second coupling section. 
     
     
         17 . The structure of  claim 10 , wherein a first sidewall of the first core in the first coupling section is angled relative to a second sidewall of the second core in the second coupling section. 
     
     
         18 . The structure of  claim 10 , wherein a first width of the first core in the first coupling section is essentially uniform and wherein a second width of the second core in the second coupling section is tapered. 
     
     
         19 . The structure of  claim 10 , wherein the second core and the multiple additional second cores are center-aligned and wherein, at least in the second coupling section, the second core has different dimensions than the multiple additional second cores. 
     
     
         20 . A structure comprising:
 a first waveguide having first end sections and a first coupling section between the first end sections, wherein the first waveguide comprises a first core; and   a second waveguide having second end sections and a second coupling section between the second end sections and adjacent to the first coupling section, wherein the second waveguide comprises:
 a second core positioned laterally adjacent to the first core; and 
 an additional second core stacked vertically with the second core, wherein, within the second coupling section, the second core and the additional second core are tapered and wherein at least one input/output port of at least one of the first core and the additional second core is tapered.