Tailored index single mode optical amplifiers and devices and systems including same

• US 6,917,729 B2
• Filed: 12/17/2003
• Issued: 07/12/2005
• Est. Priority Date: 04/11/2000
• Status: Expired due to Fees

• Current Assignee: Coherent Inc (Coherent Corp.)
• Original Assignee: Nuvonyx, Inc.
• Inventors: Faircloth, Brian O., Zediker, Mark S., Haake, John M., Priest, James A., Bott, Eric E.
• Primary Examiner(s): HEALY, BRIAN
• Application Number:
  US10/737,127
• Publication Number:
  US 20040125846A1
• Time in Patent Office: 573 Days
• Field of Search: 385 1- 3, 385/14, 385129-131, 385/37, 385/43, 385/45, 372/46, 372/45, 372/29, 372/50, 372/90, 359/334, 359/349, 359/333
• US Class Current: 385/14
• CPC Class Codes: G02B 6/12007 forming wavelength selective elements, e.g. multiplexer, demultiplexer
• CPC Class Codes: G02B 6/122 Basic optical elements, e.g. light-guiding paths
• CPC Class Codes: G02B 6/1228 Tapered waveguides, e.g. integrated spot-size transformers for coupling with fibres G02B6/305
• CPC Class Codes: G02B 6/13 Integrated optical circuits characterised by the manufacturing method
• CPC Class Codes: H01S 3/2383 Parallel arrangements
• CPC Class Codes: H01S 5/0071 for beam steering, e.g. using a mirror outside the cavity to change the beam direction
• CPC Class Codes: H01S 5/0085 for modulating the output, i.e. the laser beam is modulated outside the laser cavity
• CPC Class Codes: H01S 5/026 Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers stabilisation of output H01S5/06
• CPC Class Codes: H01S 5/0268 Integrated waveguide grating router, e.g. emission of a multi-wavelength laser array is combined by a "dragon router"
• CPC Class Codes: H01S 5/0655 Single transverse or lateral mode emission
• CPC Class Codes: H01S 5/1014 Tapered waveguide, e.g. spotsize converter H01S5/1064 takes precedence
• CPC Class Codes: H01S 5/106 varying thickness along the optical axis
• CPC Class Codes: H01S 5/1064 varying width along the optical axis
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/222 having a refractive index lower than that of the cladding layers or outer guiding layers
• CPC Class Codes: H01S 5/2231 with inner confining structure only between the active layer and the upper electrode
• CPC Class Codes: H01S 5/227 Buried mesa structure ; Striped active layer
• CPC Class Codes: H01S 5/4012 Beam combining, e.g. by the use of fibres, gratings, polarisers, prisms
• CPC Class Codes: H01S 5/4031 Edge-emitting structures
• CPC Class Codes: H01S 5/50 Amplifier structures not provided for in groups H01S5/02 - H01S5/30

Abstract

A semiconductor laser device includes a tailored index single mode power amplifier. A high-power laser system can be produced by connecting several of the tailored index single mode power amplifiers in parallel. In an exemplary case, a phase shifting device can be optically coupled to each of the tailored index single mode power amplifiers; the phase shifting devices can be controlled to ensure that the laser beams output by the tailored index single mode power amplifiers are both phase aligned and wavefront matched.

Claims

1. A semiconductor device comprising:

at least one tailored index single mode optical amplifier; and

a heat sink,

wherein the tailored index associated with the optical amplifier is produced by varying the thermal impedance characteristic of the junction at the heatsink.

2. A semiconductor device comprising at least one tailored index single mode optical amplifier,

wherein the tailored index associated with the optical amplifier is produced by varying at least two of:

a current profile applied to the optical amplifier;

the thermal impedance characteristic of a junction between the optical amplifier and a heatsink thermally coupled thereto;

impurity densities in regions of the semiconductor device adjacent to the optical amplifier;

the height of a buried rib along the optical axis as the width varies from a first to a second predetermined value; and

the height of a surface rib along the optical axis as the width varies from a first to a second predetermined value.

3. A semiconductor device comprising:

at least one tailored index single mode optical amplifier;

an input waveguide for coupling an optical signal into the optical amplifier; and

an output waveguide for coupling an amplified signal out of the optical amplifier.

4. The semiconductor device as recited in claim 3, wherein the output waveguide comprises an optical element for extracting the amplified signal out of a surface parallel to the optical axis of the optical amplifier.

5. The semiconductor device as recited in claim 4, wherein the optical element comprises a turning mirror.

6. The semiconductor device as recited in claim 4, wherein the optical element comprises a diffraction grating.

7. The semiconductor device as recited in claim 3, wherein the input waveguide comprises a tailored index waveguide.

8. The semiconductor device as recited in claim 3, wherein the input waveguide comprises a tapered waveguide.

9. The semiconductor device as recited in claim 3, wherein the semiconductor device comprises epitaxial layers, and

wherein at least one of the input waveguide and the output waveguide couples one of the optical signal and the amplified signal at a boundary plane of the optical amplifier intersecting the epitaxial layers.

10. The semiconductor device as recited in claim 9, wherein the boundary plane is not perpendicular to the optical axis of the optical amplifier.

11. A semiconductor device comprising:

a tailored index single mode optical amplifier including means for tailoring a structural characteristic associated with the optical amplifier to thereby provide the tailored index;

first coupling means for coupling an optical signal into the optical amplifier; and

second coupling means for coupling an amplified signal out of the optical amplifier.

12. The semiconductor device as recited in claim 11, wherein at least one of the first and second coupling means comprises an optical fiber.

13. The semiconductor device as recited in claim 11, wherein at least one of the first and second coupling means comprises a free space optical path portion.

14. The semiconductor device as recited in claim 11, wherein at least one of the first and second coupling means comprises a phase modulator.

18. A semiconductor device comprising:

an optical phased array having N output amplifiers.

wherein each of the output amplifiers comprises a tailored index single mode amplifier, the N output amplifiers are disposed on a single substrate, and N is an integer equal to or greater than 2, and

wherein the semiconductor device further comprises coupling elements for coupling optical signals one of into and out of the surface of the semiconductor device.

15. The semiconductor device as recited in claim 18, wherein the N tailored index single mode output amplifiers are disposed in a linear array.

16. The semiconductor device as recited in claim 15, wherein at least one of the input and output regions of the semiconductor device associated with the linear array corresponds to a facet of the semiconductor device exposing the epitaxial layers of the semiconductor device.

17. The semiconductor device as recited in claim 18, wherein the N tailored index single mode output amplifiers are disposed in a two-dimensional planar array.

19. A semiconductor device comprising:

an optical phased array having N output amplifiers,

wherein each of the output amplifiers comprises a tailored index single mode amplifier, the N output amplifiers are disposed on a single substrate, and N is an integer equal to or greater than 2, and

wherein each of the N optical amplifiers is optically coupled to one of a surface emitter and a receptor disposed on a layer of the semiconductor device.

20. A semiconductor device comprising:

a distribution network receiving an optical source signal and generating N distributed signals;

N−

1 phase modulators receiving N−

1 of the N distributed signals and generating N−

1 phase modulated signals;

an optical phased array having N output amplifiers, each of the N optical amplifiers receiving one of the N−

1 phase modulated signals or the N distributed signals,

wherein each of the output amplifiers comprises a tailored index single mode amplifier,

wherein the N output amplifiers, the N−

1 phase modulators, and the distribution network are disposed on a single substrate, and

wherein N is an integer equal to or greater than 2.

21. The semiconductor device as recited in claim 20, wherein the N tailored index single mode output amplifiers are disposed in a linear array.

22. The semiconductor device as recited in claim 21, wherein at least one of the input and output regions of the semiconductor device associated with the linear array corresponds to a facet of the semiconductor device exposing the epitaxial layers of the semiconductor device.

23. The semiconductor device as recited in claim 20, wherein each of the N−

1 phase modulators increases the collimation of the individual optical outputs of N−

1 of the N output amplifiers.

24. The semiconductor device as recited in claim 20, wherein the N−

1 phase modulators collectively improve the geometric fill factor of the combined optical outputs of the N output amplifiers.

25. The semiconductor device as recited in claim 20, wherein the N tailored index single mode output amplifiers are disposed in a two-dimensional planar array.

26. The semiconductor device as recited in claim 25, wherein the semiconductor device further comprises coupling elements for coupling optical signals one of into and out of the surface of the semiconductor device.

27. The semiconductor device as recited in claim 25, wherein each of the N optical amplifiers is optically coupled to one of a surface emitter or a receptor disposed on a layer of the semiconductor device.

28. The semiconductor device as recited in claim 25, wherein each of the N−

1 phase modulators increases the collimation of the individual optical outputs of N−

1 of the N output amplifiers.

29. The semiconductor device as recited in claim 20, wherein the N−

1 phase modulators collectively improve the geometric fill factor of the combined optical outputs of the N output amplifiers.

30. A semiconductor device comprising:

a master oscillator generating an optical source signal;

a distribution network receiving the optical source signal and generating N distributed signals;

N−

1 phase modulators receiving N−

1 of the N distributed signals and generating N−

1phase modulated signals;

an optical phased array having N output amplifiers, each of the N optical amplifiers receiving one of the N−

1 phase modulated signals or the N distributed signals,

wherein each of the output amplifiers comprises a tailored index single mode amplifier,

wherein the N output amplifiers, the N−

1 phase modulators, the distribution network, and the master oscillator are all disposed on a single substrate, and

wherein N is an integer equal to or greater than 2.

31. The semiconductor device as recited in claim 30, wherein the N tailored index single mode output amplifiers are disposed in a linear array.

32. The semiconductor device as recited in claim 31, wherein at least one of the input and output regions of the semiconductor device associated with the linear array corresponds to a facet of the semiconductor device exposing the epitaxial layers of the semiconductor device.

33. The semiconductor device as recited in claim 30, wherein each of the N−

1 phase modulators increases the collimation of the individual optical outputs of N−

1 of the N output amplifiers.

34. The semiconductor device as recited in claim 30, wherein the N−

1 phase modulators collectively improve the geometric fill factor of the combined optical outputs of the N output amplifiers.

35. The semiconductor device as recited in claim 30, wherein the N tailored index single mode output amplifiers are disposed in a two-dimensional planar array.

36. The semiconductor device as recited in claim 35, wherein the semiconductor device further comprises coupling elements for coupling optical signals one of into and out of the surface of the semiconductor device.

37. The semiconductor device as recited in claim 35, wherein each of the N optical amplifiers is optically coupled to one of a surface emitter or a receptor disposed on a layer of the semiconductor device.

38. The semiconductor device as recited in claim 35, wherein each of the N−

1 phase modulators increases the collimation of the individual optical outputs of N−

1 of the N output amplifiers.

39. The semiconductor device as recited in claim 30, wherein the N−

1 phase modulators collectively improve the geometric fill factor of the combined optical outputs of the N output amplifiers.