Integrated interferometric optical transmitter

1. An optical transmitter comprising:

a substrate;

an optical source disposed over the substrate, the optical source comprising:

a first resonating cavity including a first reflector and a third reflector, the first resonating cavity configured to output a first light beam having a wavelength λ 1 and a first optical phase along a first output optical path;

a second resonating cavity including the third reflector and a second reflector, the second resonating cavity configured to output a second light beam having a wavelength λ 2 and a second optical phase along a second output optical path; and

a first active region comprising an active material, the first active region coupled to at least one of the first and second resonating cavities,

at least one modulating electrode integrated with at least one of the first and second output optical paths; and

an optical signal combiner that interferometrically combines equally or unequally light propagating in the first and second output optical paths to generate an output optical signal.

2. The optical transmitter of claim 1 , wherein the wavelength of the first light beam is equal to the wavelength of the second light beam.

3. The optical transmitter of claim 1 , wherein the wavelength of the first light beam is within 10% of the wavelength of the second light beam.

4. The optical transmitter of claim 1 , wherein the first optical phase is correlated with the second optical phase.

5. The optical transmitter of claim 1 , wherein the first optical phase is uncorrelated with the second optical phase.

6. The optical transmitter of claim 1 , wherein the first output optical path includes a first waveguide structure and the second output optical path includes a second waveguide structure.

7. The optical transmitter of claim 6 , wherein the first active region is formed on an epitaxial layer of the substrate and the first and second waveguides are formed on the substrate in the same epitaxial layer as the first active region.

8. The optical transmitter of claim 6 , wherein the first active region is formed on an epitaxial layer of the substrate and the first and second waveguides are formed on the substrate in a different layer.

9. The optical transmitter of claim 1 , wherein the first output optical path includes a first end of a waveguide structure and the second output optical path includes a second end of the waveguide structure.

10. The optical transmitter of claim 9 , wherein the first active region is formed on an epitaxial layer of the substrate and the waveguide structure is formed on the substrate in the same epitaxial layer as the first active region.

11. The optical transmitter of claim 9 , wherein the first active region is formed on an epitaxial layer of the substrate and the waveguide structure is formed on the substrate in a different layer.

12. The optical transmitter of claim 1 , wherein the third reflector is disposed such that the first active region is between the first reflector and the third reflector.

13. The optical transmitter of claim 1 , wherein the optical source includes an optical splitter and the first and second output optical paths are a part of the optical splitter.

14. The optical transmitter of claim 13 , wherein the first active region comprises the optical splitter.

15. The optical transmitter of claim 13 , wherein the optical source further comprises a second active region, the first output optical path being coupled to the first active region and the second output optical path being coupled to the second active region.

16. The optical transmitter of claim 15 , wherein the first active region is disposed in the first output optical path between the optical splitter and the first reflector and the second active region is disposed in the second output optical path between the optical splitter and the second reflector.

17. The optical transmitter of claim 1 , wherein the first and the second light beams are single mode.

18. The optical transmitter of claim 1 , wherein the first wavelength or the second wavelength is in a range between 1500 nm and 1600 nm.

19. The optical transmitter of claim 1 , wherein the output optical signal has an optical power between about 0.1 mW and about 500 mW.

20. The optical transmitter of claim 1 , wherein the first or the second light beam has a spectral line-width between about 1 kHz and about 100 MHz.

21. The optical transmitter of claim 1 , wherein at least one of the first reflector or the second reflector has a reflectivity between about 4% and about 70%.

22. The optical transmitter of claim 1 , wherein the first reflector or the second reflector comprises a grating.

23. The optical transmitter of claim 22 , wherein the first reflector or the second reflector comprises a sampled grating.

24. The optical transmitter of claim 1 , wherein at least one the first and the second output optical paths is straight.

25. The optical transmitter of claim 1 , wherein at least one of the first and the second output optical paths is curved.

26. The optical transmitter of claim 1 , wherein an amplitude or a phase of at least one of the first and second light beams is modulated in response to an electric field applied to the at least one modulating electrode.

27. The optical transmitter of claim 1 , wherein the first active region is disposed between the first and second output optical paths such that the first and second output optical paths are disposed on either side of the first active region and connected to the first active regionby straight or curved sections.

28. The optical transmitter of claim 27 , wherein the first active region is connected to the first and second output optical paths by total internal reflection mirrors.

29. The optical transmitter of 1 , wherein the optical signal combiner is a multimode interference coupler.