Semiconductor zigzag laser and optical amplifier

• US 20030012246A1
• Filed: 07/12/2002
• Published: 01/16/2003
• Est. Priority Date: 07/12/2001
• Status: Abandoned Application

• Current Assignee: Textron Innovations Incorporated (Textron Inc)
• Original Assignee: Textron Innovations Incorporated (Textron Inc)
• Inventors: Klimek, Daniel E., Mandl, Alexander E.
• Application Number:
  US10/194,140
• Publication Number:
  US 20030012246A1
• Time in Patent Office: Days
• US Class Current: 372/70
• CPC Class Codes: H01S 5/041 Optical pumping
• CPC Class Codes: H01S 5/10 Construction or shape of the optical resonator , e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region H01S5/20 takes precedence
• CPC Class Codes: H01S 5/1082 with a special facet structure, e.g. structured, non planar, oblique
• CPC Class Codes: H01S 5/1085 Oblique facets
• CPC Class Codes: H01S 5/18 Surface-emitting [SE] lasers, e.g. having both horizontal and vertical cavities
• CPC Class Codes: H01S 5/2004 Confining in the direction perpendicular to the layer structure
• CPC Class Codes: H01S 5/50 Amplifier structures not provided for in groups H01S5/02 - H01S5/30
• CPC Class Codes: H01S 5/5018 using two or more amplifiers or multiple passes through the same amplifier

Abstract

A semiconductor structure includes a first cladding layer, a second cladding layer, and one or more semiconductor active regions. An optical resonator is formed by the inclusion of a first mirror and a second mirror at opposite ends of the structure with respect to the optical axis. One or more angled facets provide the semiconductor structure with optical coupling. The associated beam path along an optical axis within the structure is a zigzag path, which is substantially independent of the height of the active region. A signal generator and an optical amplifier may be formed with the structure. An optical modulator, multiplexer, and demultiplexer may also use the structure.

Claims

1. A semiconductor zigzag optical amplifier comprising:

a zigzag structure having a zigzag optical axis, said zigzag structure in optical communication with a first facet crossing said zigzag optical axis and a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer;

a first active region disposed between said first cladding layer and said second cladding layer; and

a means for pumping, said means for pumping providing a population inversion in said first active region.

2. The semiconductor zigzag optical amplifier of claim 1, wherein said first cladding layer and said second cladding layer each have an index of refraction greater than a region immediately exterior to said zigzag structure, and wherein an input signal travels in a zigzag path along said zigzag optical axis within said zigzag structure and is amplified by said first active region.

3. The semiconductor zigzag optical amplifier of claim 1, wherein said first facet and said second facet are part of, respectively, a first prism disposed adjacent said first cladding layer and a second prism disposed adjacent said first cladding layer or said second cladding layer.

4. The semiconductor zigzag optical amplifier of claim 1, wherein said first facet and said second facet are each formed across a portion of said first cladding layer or said second cladding layer.

5. The semiconductor zigzag optical amplifier of claim 1, wherein said first facet is part of a first prism disposed adjacent one of said first cladding layer or said second cladding layer and said angled facet is formed across a portion of said first cladding layer or said second cladding layer.

6. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes amplified spontaneous emission breaks disposed along the longitudinal axis of said semiconductor active region.

7. The semiconductor zigzag optical amplifier of claim 1, further including a substrate.

8. The semiconductor zigzag optical amplifier of claim 7, wherein said substrate is selected from the group consisting of InP, GaN, and GaAs.

9. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes a heterostructure made of a direct-gap semiconductor.

10. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes a double heterostructure made of a direct-gap semiconductor.

11. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes a quantum well.

12. The semiconductor zigzag optical amplifier of claim 11, wherein said quantum well is made from GaAs and AlGaAs.

13. The semiconductor zigzag optical amplifier of claim 11, wherein said quantum well is made from InP and InGaAsP.

14. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes one or more multiple quantum wells.

15. The semiconductor zigzag optical amplifier of claim 14, wherein said one or more multiple quantum wells are made from InP and InGaAsP.

16. The semiconductor zigzag optical amplifier of claim 14, wherein said one or more multiple quantum wells are made from GaAs and AlGaAs.

17. The semiconductor zigzag optical amplifier of claim 14, wherein said one or more multiple quantum wells are doped with a dopant selected from the group consisting of Zn, Be, Mg, and C.

18. The semiconductor zigzag optical amplifier of claim 1, wherein said first active region includes one or more quantum wires.

19. The semiconductor zigzag optical amplifier of claim 1, wherein said first facet and said second facet are parallel to one another with respect to said zigzag optical axis.

20. The semiconductor zigzag optical amplifier of claim 3, wherein said first prism has a plurality of output faces, wherein each of said plurality of output faces is angled to transmit one of a plurality of light signals having different wavelengths.

21. The semiconductor zigzag optical amplifier of claim 3, wherein said first prism has a diffraction grating formed on a surface thereof.

22. The semiconductor zigzag optical amplifier of claim 1, further comprising a second active region disposed within said gain region.

23. The semiconductor zigzag optical amplifier of claim 22, wherein said second active region is parallel to said first active region.

24. The semiconductor zigzag optical amplifier of claim 1, further comprising a plurality of active regions disposed parallel to said first active region.

25. The semiconductor zigzag optical amplifier of claim 24, wherein each of said plurality of active regions is made of a different direct-gap semiconductor.

27. The semiconductor zigzag optical amplifier of claim 26, wherein an input signal travels in a zigzag path within said zigzag structure along said zigzag optical axis and is amplified by said first active region.

29. The semiconductor zigzag laser of claim 28, wherein said first cladding layer and said second cladding layer each have an index of refraction greater than a region immediately exterior to said zigzag structure, and wherein an input signal travels in a zigzag path within said zigzag structure and is amplified by said first semiconductor active region.

30. The semiconductor zigzag laser of claim 28, wherein said first facet is provided by a prism disposed adjacent one of said first cladding layer or said second cladding layer.

31. The semiconductor zigzag laser of claim 28, wherein said first facet is formed across a portion of said first cladding layer or said second cladding layer.

32. The semiconductor zigzag laser of claim 28, wherein said first semiconductor active region includes amplified spontaneous emission breaks disposed along a longitudinal axis of said first semiconductor active region.

33. The semiconductor zigzag laser of claim 28, further including a substrate.

34. The semiconductor zigzag laser of claim 33, wherein said substrate is selected from the group consisting of InP and GaAs.

35. The semiconductor zigzag laser of claim 28, wherein said first active region includes a heterostructure made of a direct-gap semiconductor.

36. The semiconductor zigzag laser of claim 28, wherein said first active region includes a double heterostructure made of a direct-gap semiconductor.

37. The semiconductor zigzag laser of claim 28, wherein said first active region includes a quantum well.

38. The semiconductor zigzag laser of claim 37, wherein said quantum well is made from GaAs and AlGaAs.

39. The semiconductor zigzag laser of claim 37, wherein said quantum well is made from InP and InGaAsP.

40. The semiconductor zigzag laser of claim 28, wherein said first active region includes one or more multiple quantum wells.

41. The semiconductor zigzag laser of claim 40, wherein said one or more multiple quantum wells are made from InP and InGaAsP.

42. The semiconductor zigzag laser of claim 40, wherein said one or more multiple quantum wells are made from GaAs and AlGaAs.

43. The semiconductor zigzag laser of claim 40, wherein said one or more multiple quantum wells are doped with a dopant selected from the group consisting of Zn, Be, Mg, and C.

44. The semiconductor zigzag laser of claim 28, wherein said first active region includes one or more quantum wires.

45. The semiconductor zigzag laser of claim 28, wherein said first active region includes one or more quantum dots.

46. The semiconductor zigzag laser of claim 33, wherein said substrate is adjacent said first cladding layer or said second cladding layer.

49. The optical modulation system of claim 48, wherein said first cladding layer and said second cladding layer each have an index of refraction greater than a region immediately exterior to said zigzag structure, and wherein an input signal travels in a zigzag path within said zigzag structure and is amplified by said first semiconductor active region.

50. The optical modulation system of claim 48, wherein said signal modulator is external to said optical resonator.

51. The optical modulation system of claim 48, said system further including a substrate disposed adjacent said first cladding layer.

52. The optical modulation system of claim 48, wherein said signal modulator includes a piezoelectric element.

53. The optical modulation system of claim 52, wherein said signal modulator further includes a prism disposed adjacent said piezoelectric element.

54. The optical modulation system of claim 48, wherein said signal modulator is selected from the group consisting of a Pockels cell, a Kerr cell, and a Mach-Zehnder interferometer.

55. The optical modulation system of claim 51, wherein said signal modulator is disposed on said substrate.

56. The optical modulation system of claim 55, wherein said signal modulator is a Mach-Zehnder interferometer.

59. The method of modulating an optical signal of claim 58, wherein said step of modulating said signal further includes modulating said signal from a state of substantially zero amplitude to a state of maximum amplitude.

26. A semiconductor zigzag optical amplifier comprising:

a zigzag structure having a zigzag-optical axis in optical communication with a first facet crossing said zigzag optical axis and a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer, wherein said zigzag structure has an index of refraction in said first cladding layer and said second cladding layer greater than a region immediately exterior to said zigzag structure;

a first active region disposed between said first cladding layer and said second cladding layer; and

a current source connected to said zigzag structure and operable to provide a pump current to said first active region for providing a population inversion in said first active region.

28. A semiconductor zigzag laser comprising:

an optical resonator including a zigzag structure having a zigzag optical axis, wherein said zigzag structure is in optical communication with a first facet crossing said zigzag optical axis, said zigzag structure in communication with a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer, said first facet having a first mirror with a first reflectivity, said second facet having a second mirror with a second reflectivity, wherein said first reflectivity does not equal said second reflectivity, and wherein said first mirror is parallel to said second mirror with respect to said zigzag optical axis;

a first semiconductor active region disposed between said first cladding layer and said second cladding layer; and

a means for pumping, said means for pumping providing a population inversion in said first semiconductor active region.

47. A semiconductor zigzag laser comprising:

an optical resonator including a zigzag structure having a zigzag optical axis, wherein said zigzag structure is in optical communication with a first facet crossing said zigzag optical axis, said zigzag structure in communication with a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer, said first facet having a first mirror with a first reflectivity, said second facet having a second-mirror with a second reflectivity, wherein said first reflectivity does not equal said second reflectivity, and wherein said first mirror is parallel to said second mirror with respect to said zigzag optical axis;

a first semiconductor active region disposed between said first cladding layer and said second cladding layer; and

a current source connected to said zigzag structure for providing a population inversion in said first semiconductor active region.

48. An optical modulation system comprising:

an optical resonator including a zigzag structure having a zigzag optical axis, wherein said zigzag structure is in optical communication with a first facet crossing said zigzag optical axis, said zigzag structure in communication with a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer, said first facet having a first mirror with a first reflectivity, said second facet having a second mirror with a second reflectivity, wherein said first reflectivity does not equal said second reflectivity, and wherein said first mirror is parallel to said second mirror with respect to said zigzag optical axis;

a first active region disposed between said first cladding layer and said second cladding layer;

a means for pumping, said means for pumping providing a population inversion in said first active region;

a signal modulator in optical communication with said optical resonator; and

a modulated optical output signal.

57. An optical modulation system comprising:

an optical resonator including a zigzag structure having a zigzag optical axis, wherein said zigzag structure is in optical communication with a first facet crossing said zigzag optical axis, said zigzag structure in communication with a second facet crossing said zigzag optical axis, said zigzag structure having a first cladding layer and a second cladding layer, said first facet having a first mirror with a first reflectivity adjacent thereto, said second facet having a second mirror with a second reflectivity adjacent thereto, wherein said first reflectivity does not equal said second reflectivity, and wherein said first mirror is parallel to said second mirror with respect to said zigzag optical axis;

a first active region disposed between said first cladding layer and said second cladding layer, wherein an input signal travels in a zigzag path within said zigzag structure and is amplified by said first semiconductor active region;

a current source connected to said zigzag structure and providing a population inversion in said first active region;

a signal modulator in optical communication with said zigzag structure; and

a modulated optical output signal.

58. A method of modulating an optical signal comprising the steps of:

generating a signal from a semiconductor zigzag signal generator; and

modulating said signal with an optical modulator.

60. A semiconductor zigzag demultiplexing system for use in a communication systems that use wavelength division multiplexing, said semiconductor zigzag demultiplexing system comprising:

a zigzag structure having a zigzag optical axis, said zigzag structure in optical communication with a first facet crossing said zigzag optical axis and a second facet crossing said zigzag optical axis, said semiconductor gain region having a first cladding layer and a second cladding layer;

a first semiconductor active region disposed between said first cladding layer and said second cladding layer;

a current source connected to said optical resonator providing a population inversion in said first semiconductor active region;

an input optical fiber in optical communication with said first facet, said optical fiber carrying an input signal including a plurality of separate carrier signals each of a different frequency, wherein each of said plurality of separate carrier signals travels in a separate zigzag path within said gain region and is amplified by said first semiconductor active region; and

a plurality of output optical fibers in optical communication with said second facet, wherein each of said plurality of output optical fibers outputs one of said plurality of separate carrier signals.

61. A semiconductor zigzag multiplexing system for use in a communication systems that use wavelength-division multiplexing, said semiconductor zigzag multiplexing system comprising:

a zigzag structure having a zigzag optical axis, said zigzag structure in optical communication with a first facet crossing said zigzag optical axis and a second facet crossing said zigzag optical axis, said semiconductor gain region having a first cladding layer and a second cladding layer;

a first semiconductor active region disposed between said first cladding layer and said second cladding layer;

a current source connected to said zigzag structure providing a population inversion in said first semiconductor active region;

an plurality of input optical fibers in optical communication with said first facet, each of said plurality of optical fibers operable to carry an input carrier signal of a different frequency, wherein each separate carrier signal travels in a separate zigzag path within said gain region and is amplified by said first semiconductor active region; and

an output optical fiber in optical communication with said second facet, wherein each separate carrier signal so amplified enters into said output optical fiber.

62. A semiconductor laser comprising:

an active region between a first cladding layer and a second cladding layer; and

a first facet and a second facet in optical communication via a zigzag optical axis, wherein the zigzag optical axis passes through the first cladding layer, the active region and the second cladding layer.

63. A semiconductor laser comprising:

at least one active region between a first cladding layer and a second cladding layer; and

a first facet in optical communication with a second facet along a zigzag optical axis, wherein the zigzag optical axis passes through the first cladding layer, the at least one active region, and the second cladding layer.

64. A semiconductor laser comprising:

at least one active region between a first cladding layer and a second cladding layer; and

a first facet in optical communication with a second facet such that when the semiconductor laser is energized a zigzag optical axis is created from the first facet through the at least one active region, to the second facet.