Optical waveguide and optical device based on the same

1. An optical waveguide, comprising:

a core layer positioned on a substrate, and including patterns positioned in a first region and a second region, the core layer having a lower side which faces the substrate and an upper side opposite to the lower side;

a clad layer positioned on the upper side of the core layer; and

a wavelength adjusting unit positioned in the first region between the substrate and the clad layer, and configured to adjust a wavelength of an optical signal propagated through patterns passing through the first region based on received electric energy,

wherein the clad layer includes a material having a Thermo-Optic Coefficient (TOC) with an opposite sign to that of a material included in the core layer,

wherein the core layer includes a silicon material having a positive TOC, and

wherein the clad layer includes:

a first clad layer positioned on the upper side of the core layer in the first region, and including a material having a smaller TOC than that of the silicon material included in the core layer; and

a second clad layer positioned on the upper side of the core layer in the second region and including a material having a negative TOC.

2. The optical waveguide of claim 1 , wherein the first region is smaller than the second region.

3. The optical waveguide of claim 1 , wherein the wavelength adjusting unit generates heat based on the received electric energy, and provides the generated heat to the patterns passing through the first region to adjust a wavelength of an optical signal propagated through the patterns passing through the first region.

4. The optical waveguide of claim 1 , further comprising:

a slap waveguide positioned between the substrate and the core layer.

5. The optical wavelength of claim 4 , wherein the wavelength adjusting unit includes a first wavelength adjusting unit on one side of the patterns in the first region and a second wavelength adjusting unit on the other side of the patterns in the first region, and the first and second wavelength adjusting units have a height greater than a thickness of the slap waveguide.

6. The optical waveguide of claim 1 , wherein the optical waveguide is used in an optical device based on the optical waveguide.

7. The optical waveguide of claim 1 , wherein the wavelength adjusting unit includes a first wavelength adjusting unit on one side of the patterns in the first region and a second wavelength adjusting unit on the other side of the patterns in the first region, and the first and second wavelength adjusting units are formed of a same material.

8. An optical device based on an optical waveguide, comprising:

a substrate; and

a ring resonator positioned on the substrate,

wherein the ring resonator includes:

a core layer positioned on the substrate, and including at least one ring waveguide positioned in a first region and a second region, the core layer having a lower side which faces the substrate and an upper side opposite to the lower side;

a clad layer positioned on the upper side of the core layer; and

a wavelength adjusting unit positioned in the first region between the substrate and the clad layer, and configured to adjust a wavelength of an optical signal propagated through a ring waveguide passing through the first region based on received electric energy,

wherein the clad layer includes a material having a Thermo-Optic Coefficient (TOC) with an opposite sign to that of a material included in the core layer,

wherein the core layer includes a silicon material having a positive TOC, and

wherein the clad layer includes:

a first clad layer positioned on the upper side of the core layer in the first region, and including a material having a smaller TOC than that of the silicon material included in the core layer; and

a second clad layer positioned on the upper side of the core layer in the second region and including a material having a negative TOC.

9. The optical device of claim 8 , wherein the first region is smaller than the second region.

10. The optical device of claim 8 , wherein the wavelength adjusting unit generates heat based on the received electric energy, and provides the generated heat to the ring waveguide passing through the first region to adjust a wavelength of an optical signal propagated through the ring waveguide passing through the first region.

11. The optical device of claim 8 , further comprising:

a slap waveguide positioned between the substrate and the core layer.

12. The optical device of claim 11 , wherein the wavelength adjusting unit includes a first wavelength adjusting unit on one side of the patterns in the first region and a second wavelength adjusting unit on the other side of the patterns in the first region, and the first and second wavelength adjusting units have a height greater than a thickness of the slap waveguide.

13. The optical device of claim 8 , wherein the wavelength adjusting unit includes a first wavelength adjusting unit on one side of the patterns in the first region and a second wavelength adjusting unit on the other side of the patterns in the first region, and the first and second wavelength adjusting units are formed of a same material.

14. The optical device of claim 8 , when taken from a plan view, the first region is a region corresponding to a range of a predetermined acute center angle relative to a center of a circle formed by the at least one ring waveguide.

15. The optical device of claim 14 , when taken from a plan view, the wavelength adjusting unit extends in the first region along the at least one ring waveguide and forms a center angle relative to the center of the circle not greater than the predetermined acute center angle of the first region.