Optical device including a grated optical waveguide to improve modulation efficiency
Examples described herein relate to an optical device that entails phase shifting an optical signal. The optical device includes an optical waveguide having a first semiconductor material region and a second semiconductor material region formed adjacent to each other and defining a junction therebetween. Further, the optical device includes an insulating layer formed on top of the optical waveguide. Moreover, the optical device includes a III-V semiconductor layer formed on top of the insulating layer causing an optical mode of an optical signal passing through the optical waveguide to overlap with the first semiconductor material region, the second semiconductor material region, the insulating layer, and the III-V semiconductor layer thereby resulting in a phase shift in the optical signal passing through the optical waveguide.
1. An optical device comprising:
an optical waveguide comprising a grating formed along a length of the optical waveguide, wherein the optical waveguide is an annular resonator, and wherein the length of the optical waveguide is a circumferential length of the optical waveguide;
an insulating layer formed on a first side of the optical waveguide, wherein a first side of the insulating layer is disposed proximate to the first side of the optical waveguide; and
an electrically conductive layer formed on a second side of the insulating layer, wherein the optical waveguide, the insulating layer, and the electrically conductive layer form a waveguide integrated capacitor, wherein the grating in the optical waveguide causes an optical mode of an optical signal passing through the optical waveguide to overlap with the optical waveguide and the electrically conductive layer thereby resulting in an enhanced modulation efficiency via the waveguide integrated capacitor.
2. The optical device of claim 1 , wherein the optical waveguide is made of a semiconductor material, wherein the grating comprises a plurality of parallel ridges of the semiconductor material, and wherein the semiconductor material comprises a first type doping.
3. The optical device of claim 2 , wherein a spacing between adjacent ridges of the plurality of parallel ridges is uniform.
4. The optical device of claim 3 , wherein the semiconductor material is Silicon.
5. The optical device of claim 1 , wherein the optical device is disposed in an optical transceiver.
6. The optical device of claim 5 , wherein the optical transceiver is disposed in a server, a storage device, a router, a network switch, or an access point.
7. The optical device of claim 1 , wherein the electrically conductive layer is a semiconductor material comprising a second-type doping.
8. The optical device of claim 1 , wherein the electrically conductive layer is a III-V semiconductor material comprising a second-type doping.
9. The optical device of claim 1 , wherein the optical waveguide, due to the presence of the grating, comprises alternately formed first optical waveguide sections and second optical waveguide sections.
10. The optical device of claim 9 , wherein the optical waveguide, in the first optical waveguide sections, is wider than in the second optical waveguide sections.
11. An electronic system, comprising:
a processing resource;
a storage medium communicatively coupled to the processing resource; and
a photonic integrated circuit communicatively coupled to the processing resource and comprising an optical device, wherein the optical device comprises:
an optical waveguide comprising a grating formed along a length of the optical waveguide, wherein the optical waveguide is an annular resonator, and wherein the length of the optical waveguide is a circumferential length of the optical waveguide;
an insulating layer formed on a first side of the optical waveguide, wherein a first side of the insulating layer is disposed proximate to the first side of the optical waveguide; and
an electrically conductive layer formed on a second side of the insulating layer, wherein the optical waveguide, the insulating layer, and the electrically conductive layer form a waveguide integrated capacitor, wherein the grating in the optical waveguide causes an optical mode of an optical signal passing through the optical waveguide to overlap with the optical waveguide and the electrically conductive layer thereby resulting in an enhanced modulation efficiency via the waveguide integrated capacitor.
12. The electronic system of claim 11 , wherein the optical waveguide, due to the presence of the grating, comprises alternately formed first optical waveguide sections and second optical waveguide sections, and wherein the optical waveguide, in the first optical waveguide sections, is wider than in the second optical waveguide sections.
13. The electronic system of claim 11 , wherein the optical waveguide is made of a semiconductor material, wherein the grating comprises a plurality of parallel ridges of the semiconductor material, and wherein the semiconductor material comprises a first type doping.
14. The electronic system of claim 11 , wherein the electrically conductive layer is a III-V semiconductor material comprising a second-type doping.
15. A method of fabricating an optical device, comprising:
providing a substrate comprising a device layer;
forming an optical waveguide in the device layer, wherein forming the optical waveguide comprises forming a grating along a length of the optical waveguide, wherein the optical waveguide is an annular resonator, and wherein the length of the optical waveguide is a circumferential length of the optical waveguide;
forming an insulating layer on a first side of the optical waveguide, wherein a first side of the insulating layer is disposed proximate to the first side of the optical waveguide; and
forming an electrically conductive layer on a second side of the insulating layer, wherein the optical waveguide, the insulating layer, and the electrically conductive layer form a waveguide integrated capacitor, wherein the grating in the optical waveguide causes an optical mode of an optical signal passing through the optical waveguide to overlap with the optical waveguide and the electrically conductive layer thereby resulting in an enhanced modulation efficiency via the waveguide integrated capacitor.
16. The method of claim 15 , wherein forming the grating comprises forming a plurality of parallel ridges in the device layer to alternately create first optical waveguide sections and second optical waveguide sections in the device layer.
17. The method of claim 16 , wherein the optical waveguide, in the first optical waveguide sections, is wider than in the second optical waveguide sections.