Silicon photonic heater-modulator

1. A photonic modulator comprising:

a disk resonator having a central axis extending along a thickness direction of the disk resonator,

wherein the disk resonator includes a modulator portion and a heater portion, the modulator portion extending in an arc around the central axis, a PN junction of the modulator portion being substantially normal to the central axis; and

wherein the disk resonator has an inner region and an outer region, the modulator portion is disposed in the outer region, the modulator portion has at least two ohmic contact regions, the heater portion has at least two ohmic contact regions, and the heater portion, the heater ohmic contact regions, and the modulator ohmic contact regions are disposed in the inner region of the disk resonator.

2. The photonic modulator of claim 1 , wherein the disk resonator is formed of at least one of silicon, silicon nitride, indium phosphide, germanium, silica, fused quartz, sapphire, alumina, glass, gallium arsenide, silicon carbide, lithium niobate, silicon on insulator, germanium on insulator and silicon germanium.

3. The photonic modulator of claim 1 , wherein the arc around the central axis of the disk resonator through which the modulator portion extends is equal to between about π/4 radians to about 2π radians.

4. The photonic modulator of claim 1 , wherein the heater portion of the disk resonator includes an integral resistive heating element.

5. The photonic modulator of claim 1 , wherein the disk resonator includes an isolation region between the modulator portion and the heater portion to substantially electrically isolate the modulator portion from the heater portion.

6. The photonic modulator of claim 1 , wherein the modulator portion includes a plurality of modulator portions, the plurality of modulator portions spaced apart from each other and extending in respective arcs around the central axis.

7. The photonic modulator of claim 1 , wherein the modulator portion includes:

a PN junction region including the PN junction, the PN junction region extending in the arc around the central axis, and

first and second ohmic contact regions adjacent to the PN junction region, the first and second ohmic contact regions having opposite doping concentrations.

8. The photonic modulator of claim 7 , wherein the disk resonator includes a surface substantially normal to the central axis, the first and second ohmic contact regions being arranged adjacent to each other and parallel to the surface of the disk resonator.

9. The photonic modulator of claim 7 , wherein the first and second ohmic contact regions are arranged adjacent to each other and parallel to the central axis of the disk resonator.

10. The photonic modulator of claim 1 , wherein an operating point of the disk resonator is tunable using a thermo-optic effect via the heater portion.

11. The photonic modulator of claim 1 , wherein the photonic modulator is modulated by at least one of carrier injection or carrier depletion via the modulator portion.

12. A method of forming a photonic modulator, the method comprising:

forming a disk resonator, the disk resonator having a central axis extending along a thickness direction of the disk resonator;

forming a heater portion in a first region of the disk resonator; and

forming a modulator portion in a second region of the disk resonator such that the modulator portion extends in an arc around the central axis of the disk resonator, a PN junction of the modulator portion being formed substantially normal to the central axis;

wherein the disk resonator is formed with an inner region and an outer region, the modulator portion is disposed in the outer region, the modulator portion is formed with at least two ohmic contact regions, the heater portion is formed with at least two ohmic contact regions, and the heater portion, the heater ohmic contact regions, and the modulator ohmic contact regions are formed in the inner region of the disk resonator.

13. The method of claim 12 , wherein the arc around the central axis of the disk resonator through which the modulator portion extends is equal to between about π/4 radians to about 2π radians.

14. The method of claim 12 , wherein the forming of the heater portion includes doping a material of the first region of the disk resonator to form a resistive heating element.

15. The method of claim 12 , wherein the forming of the modulator portion includes forming a plurality of modulator portions in the disk resonator, the plurality of modulator portions being spaced apart from each other and extending in respective arcs around the central axis.

16. The method of claim 12 , further comprising forming an isolation region in the disk resonator between the modulator portion and the heater portion to substantially electrically isolate the modulator portion from the heater portion.

17. The method of claim 12 , wherein the forming of the modulator region includes:

forming a PN junction region including the PN junction, the PN junction region extending in the arc around the central axis, and

forming first and second ohmic contact regions adjacent to the PN junction region, the first and second ohmic contact regions having opposite doping concentrations.

18. The method of claim 17 , wherein the disk resonator includes a surface substantially normal to the central axis, the first and second ohmic contact regions being arranged adjacent to each other and parallel to the surface of the disk resonator.

19. The method of claim 17 , wherein the first and second ohmic contact regions are arranged adjacent to each other and parallel to the central axis of the disk resonator.

20. A method of modulating an input optical signal, the method comprising:

providing the input optical signal to a waveguide;

coupling the input optical signal to a disk resonator via the waveguide, the disk resonator including a modulator portion and a heater portion, the modulator portion extending in an arc around a central axis of the disk resonator which extends along a thickness direction of the disk resonator, a PN junction of the modulator portion being substantially normal to the central axis;

setting an operating point of the disk resonator by the heater portion;

modulating the input optical signal by the modulator portion to form an output optical signal;

coupling the output optical signal from the disk resonator to the waveguide; and

transmitting the output optical signal via the waveguide;

wherein the disk resonator has an inner region and an outer region, the modulating step is performed by applying an electric signal to at least two ohmic contact regions situated in the inner region resulting in the activation of a modulator portion disposed in the outer region, and the operating-point-setting step is performed by applying an electric signal to at least two further ohmic contact regions situated in the inner region resulting in the activation of a heater portion disposed in the inner region of the disk resonator.