Edge coupler

Patent metadata

Field	Value
Publication number	US-9588298-B2
Application number	US-201514798780-A
Country	US
Kind code	B2
Filing date	Jul 14, 2015
Priority date	Jun 4, 2015
Publication date	Mar 7, 2017
Grant date	Mar 7, 2017

Abstract

A composite optical waveguide is constructed using an array of waveguide cores, in which one core is tapered to a larger dimension, so that all the cores are used as a composite input port, and the one larger core is used as an output port. In addition, transverse couplers can be fabricated in a similar fashion. The waveguide cores are preferably made of SiN. In some cases, a layer of SiN which is provided as an etch stop is used as at least one of the waveguide cores. The waveguide cores can be spaced away from a semiconductor layer so as to minimize loses.

First claim

What is claimed is:

1. A composite waveguide, comprising:
a first group of waveguide cores on a substrate, said first group of waveguide cores having an optical propagation direction, each of said first group of waveguide cores having at a respective first end thereof a first cross section defined by two dimensions measured along orthogonal coordinates and having at a respective second end thereof a second cross section defined by two dimensions measured along orthogonal coordinates;
said first group of waveguide cores having an input port comprising at least one of:
said respective first ends together comprising said optical input port for directed illumination, and
a segment of one or more of said first group of waveguide cores comprising said optical input port for evanescent waves; and

said first group of waveguide cores having an output port comprising at least one of:
said respective second ends comprising said output port for directed illumination; and
a segment of one or more of said first group of waveguide cores comprising said optical output port for evanescent waves.

2. The composite waveguide of claim 1 , wherein said substrate is a semiconductor chip.

3. The composite waveguide of claim 1 , wherein one or more of said first group of waveguide cores has a different second cross section than the second cross section of each of the remaining ones of said first group of waveguide cores.

4. The composite waveguide of claim 1 , configured to operate bidirectionally.

5. The composite waveguide of claim 1 , wherein at least one of said first end and said second end is configured as a coupler selected from the group of couplers consisting of a butt coupler, a taper coupler and an evanescent coupler.

6. The composite waveguide of claim 1 , wherein all of said first group of waveguide cores having substantially equal first cross sections.

7. The composite waveguide of claim 1 , wherein at least two of said first group of waveguide cores have unequal first cross sections.

8. The composite waveguide of claim 1 , wherein said first group of waveguide cores disposed in an array are disposed in a one-dimensional array.

9. The composite waveguide of claim 1 , wherein said first group of waveguide cores disposed in an array are disposed in a two-dimensional array.

10. The composite waveguide of claim 1 , wherein said first group of waveguide cores comprise a material selected from the group of materials consisting of crystalline silicon, poly-silicon, amorphous silicon, silicon nitride, silicon oxynitride, silicon dioxide, doped silicon dioxide and a polymer.

11. The composite waveguide of claim 10 , wherein said first cross section defined by two dimensions measured along orthogonal coordinates has a first dimension and a second dimension each no larger than 1 micron.

12. The composite waveguide of claim 1 , wherein said respective first end of each of said first group of waveguide cores is located at a facet.

13. The composite waveguide of claim 12 , wherein said facet is a facet selected from the group of facets consisting of etched facets, polished facets, sawed facets, angled facets and curved facets.

14. The composite waveguide of claim 1 , wherein said respective first end of each of said first group of waveguide cores is located within 50 microns of a facet.

15. The composite waveguide of claim 1 , further comprising:
a second group of waveguide cores having a second optical propagation direction, said second group of waveguide cores disposed on said substrate, said second group of waveguide cores displaced from said first group of waveguide cores in a direction transverse to said optical propagation direction of said first group of waveguide cores, said second group of waveguide cores in optical communication with said first group of waveguide cores;
each of said second group of waveguide cores having at a respective first end thereof a first cross section defined by two dimensions measured along orthogonal coordinates and at a respective second end thereof a second cross section defined by two dimensions measured along orthogonal coordinates;
said second group of waveguide cores having an input port comprising at least one of:
said respective first ends together comprising said optical input port for directed illumination, and
a segment of one or more of said second group of waveguide cores comprising said optical input port for evanescent waves; and
said second group of waveguide cores having an output port comprising at least one of:
said respective second ends comprising said output port for directed illumination, and
a segment of one or more of said second group of waveguide cores comprising said optical output port for evanescent waves.

16. The composite waveguide of claim 15 , wherein one or more of said second group of waveguide cores has a different second cross section than the second cross section of each of the remaining ones of said second group of waveguide cores.

17. The composite waveguide of claim 15 , configured to operate bidirectionally.

18. The composite waveguide of claim 15 , wherein at least one of said first end and said second end is configured as a coupler selected from the group of couplers consisting of a butt coupler, a taper coupler and an evanescent coupler.

19. The composite waveguide of claim 15 , wherein said second group of waveguide cores is configured to provide an optical signal at a location displaced in said transverse direction from said optical input port of said first group of waveguide cores.

20. The composite waveguide of claim 15 , wherein said second group of waveguide cores comprise a material selected from the group of materials consisting of crystalline silicon, poly-silicon, amorphous silicon, silicon nitride, silicon oxynitride, silicon dioxide, doped silicon dioxide and a polymer.

21. The composite waveguide of claim 20 , wherein said first cross section defined by two dimensions measured along orthogonal coordinates has a first dimension and a second dimension each no larger than 1 micron.

22. The composite waveguide of claim 15 , wherein said respective first end of each of said second group of waveguide cores is located at a facet.

23. The composite waveguide of claim 22 , wherein said facet is a facet selected from the group of facets consisting of etched facets, polished facets, sawed facets, angled facets and curved facets.

24. The composite waveguide of claim 15 , wherein said respective first end of each of said second group of waveguide cores is located within 50 microns of a facet.

25. The composite waveguide of claim 15 , wherein said second optical propagation direction is parallel to said optical propagation direction of said first group of waveguide cores.

26. A composite waveguide having a first group of waveguide cores on a substrate, said first group of waveguide cores having an optical propagation direction, each of said first group of waveguide cores having at a respective first end thereof a first cross section defined by two dimensions measured along orthogonal coordinates and having at a respective second end thereof a second cross section defined by two dimensions measured along orthogonal coordinates;
wherein the improvement comprises:
said first group of waveguide cores having an input port comprising at least one of:
said respective first ends together comprising said optical input port for directed

Assignees

• Coriant Advanced Tech Llc
• Elenion Tech Llc

Inventors

• Novack Ari
• Shi Ruizhi
• Hochberg Michael J
• Baehr-Jones Thomas

Classifications

• G02B6/29332

  Wavelength selective couplers, i.e. based on evanescent coupling between light guides, e.g. fused fibre couplers with transverse coupling between fibres having different propagation constant wavelength dependency · CPC title

• G02B6/305 Primary

  and having an integrated mode-size expanding section, e.g. tapered waveguide · CPC title

• G02B6/12002

  Three-dimensional structures · CPC title

• G02B2006/12121

  Laser · CPC title

• G02B6/1228

  Tapered waveguides, e.g. integrated spot-size transformers (for coupling with fibres G02B6/305) · CPC title