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A nonlinear polarization amplifier stage includes a gain medium operable, to receive a multiple wavelength optical signal. The amplifier stage also includes a pump assembly operable to generate at least one pump wavelength for introduction to the gain medium. The amplifier stage further includes a c

A nonlinear polarization amplifier stage includes a gain medium operable, to receive a multiple wavelength optical signal. The amplifier stage also includes a pump assembly operable to generate at least one pump wavelength for introduction to the gain medium. The amplifier stage further includes a coupler operable to introduce the at least one pump wavelength to the gain medium to facilitate amplification of at least a portion of the multiple wavelength optical signal through nonlinear polarization. In one particular embodiment, at least a wavelength or an intensity of the at least one pump wavelength is manipulated to affect the shape of a gain curve associated with the multiple wavelength optical signal in the amplifier stage.

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1. A Raman amplifier stage comprising:a Raman gain medium operable to receive a multiple wavelength optical signal;a pump assembly operable to generate at least one pump wavelength for introduction to the gain medium, the pump assembly comprising a light source operable to generate the at least one

1. A Raman amplifier stage comprising:a Raman gain medium operable to receive a multiple wavelength optical signal;a pump assembly operable to generate at least one pump wavelength for introduction to the gain medium, the pump assembly comprising a light source operable to generate the at least one pump wavelength at a desired intensity by controlling a drive current supplied to the light source; anda coupler operable to introduce the at least one pump wavelength to the gain medium to facilitate Raman amplification of at least a portion of the multiple wavelength optical signal;wherein the pump assembly controls at least an intensity of the at least one pump wavelength to affect the shape of a gain curve associated with the multiple wavelength optical signal in the Raman amplifier stage by controlling the current supplied to the light source. 2. The Raman amplifier stage of claim 1, wherein the gain medium comprises a distributed gain medium. 3. The Raman amplifier stage of claim 1, wherein the gain medium comprises an optical fiber. 4. The Raman amplifier stage of claim 1, wherein the pump assembly operates to generate a plurality of pump wavelengths. 5. The Raman amplifier stage of claim 4, wherein the intensities of at least some of the plurality of pump wavelengths are controlled by the pump assembly to affect the shape of the gain curve associated with the multiple wavelength optical signal in the amplifier stage. 6. The Raman amplifier stage of claim 4, further comprising a wavelength selector operable to select one or more of the plurality of pump wavelengths for application to the gain medium. 7. The Raman amplifier stage of claim 6, wherein the wavelength selector comprises a wavelength selecting element selected from the group consisting of gratings and one or more Fabry-Perot wavelength filters. 8. The Raman amplifier stage of claim 4, wherein the pump assembly comprises an array of laser diodes. 9. The Raman amplifier stage of claim 4, wherein the pump assembly comprises:a pump laser having an output port and producing a pump beam; anda bandwidth adding mirror connected to said output port to generate a broadened pump spectrum. 10. The Raman amplifier stage of claim 9, wherein said bandwidth adding mirror includes a polarization controller. 11. The Raman amplifier stage of claim 9, wherein the bandwidth adding mirror includes a phase modulator. 12. The Raman amplifier stage of claim 9, wherein the bandwidth adding mirror includes an amplitude modulator. 13. The Raman amplifier stage of claim 9, wherein the pump laser comprises a cladding pumped fiber laser. 14. The Raman amplifier stage of claim 13, wherein the cladding pumped fiber laser is driven by a modulated drive signal. 15. The Raman amplifier stage of claim 4, wherein the plurality of pump wavelengths contribute to a pump spectrum comprising a plurality of peaks. 16. The Raman amplifier stage of claim 15, wherein the plurality of peaks comprise at least three (3) peaks. 17. The Raman amplifier stage of claim 15, wherein the plurality of peaks comprise at least four (4) peaks. 18. The Raman amplifier stage of claim 15, wherein the at least two of the plurality of peaks are separated by a line width of at least one of the peaks at one half power of that peak. 19. The Raman amplifier stage of claim 15, wherein at least two of the peaks comprise different amplitudes. 20. The Raman amplifier stage of claim 15, wherein each of the peaks comprises an amplitude within ten (10) decibels of each of the others of the plurality of peaks. 21. The Raman amplifier stage of claim 15, wherein each peak resides at a different center wavelength. 22. The Raman amplifier stage of claim 15, wherein each of the plurality of peaks is spaced from all adjacent peaks by a substantially uniform wavelength spacing. 23. The Raman amplifier stage of claim 15, wherein a wavelength spacing between a first pair of adjacent peaks of the plurality of peaks is different than a wavelength spac ing between a second pair of adjacent peaks of the plurality of peaks. 24. The Raman amplifier stage of claim 1, wherein the pump assembly comprises a pump laser current modulator. 25. The Raman amplifier stage of claim 1, wherein the intensity of the at least one pump wavelength is controlled to provide a more flat gain curve associated with the multiple wavelength optical signal in the amplifier stage. 26. The Raman amplifier stage of claim 1, further comprising a gain flattening element coupled to the gain medium and operable to reduce variations in amplitude as a function of wavelength of the multiple wavelength optical signal output from the gain medium. 27. The Raman amplifier stage of claim 1, further comprising:an input port capable of receiving the multiple wavelength optical signal; andan output port capable of communicating the amplified multiple wavelength optical signal. 28. A method of controlling the shape of a gain curve of a Raman amplifier stage, comprising:receiving a multiple wavelength signal at a Raman gain medium of a Raman amplifier stage;manipulating an intensity of a pump wavelength; andintroducing the pump wavelength to the gain medium to facilitate Raman amplification of at least a portion of the multiple wavelength signal over at least a portion of the gain medium;wherein the shape of the gain curve for the amplifier stage is determined at least in part based on the manipulation of the intensity of the pump wavelength. 29. The method of claim 28, wherein the pump wavelength comprises a multiple wavelength pump signal comprising a plurality of pump wavelengths. 30. The method of claim 29, wherein manipulating at least an intensity of the pump wavelength comprises manipulating at least an intensity of at least some of a plurality of pump wavelengths. 31. The method of claim 29, wherein the intensities of at least some of the plurality of pump wavelengths are manipulated to affect the shape of the gain curve associated with the multiple wavelength optical signal in the amplifier stage. 32. The method of claim 29, wherein the plurality of pump wavelengths contribute to a pump spectrum comprising a plurality of peaks. 33. The method of claim 32, wherein the plurality of peaks comprise at least three (3) peaks. 34. The method of claim 32, wherein the plurality of peaks comprise at least four (4) peaks. 35. The method of claim 32, wherein the at least two of the plurality of peaks are separated by a line width of at least one of the peaks at one half power of that peak. 36. The method of claim 32, wherein at least two of the peaks comprise different amplitudes. 37. The method of claim 32, wherein each of the peaks comprises an amplitude within ten (10) decibels of each of the others of the plurality of peaks. 38. The method of claim 32, wherein each peak resides at a different center wavelength. 39. The method of claim 32, wherein each of the plurality of peaks is spaced from all adjacent peaks by a substantially uniform wavelength spacing. 40. The method of claim 32, wherein a wavelength spacing between a first pair of adjacent peaks of the plurality of peaks is different than a wavelength spacing between a second pair of adjacent peaks of the plurality of peaks. 41. The method of claim 28, wherein the shape of the gain curve for the amplifier stage is determined at least in part based on a selection of a wavelength of the pump wavelength. 42. The method of claim 41, wherein selecting a wavelength of the pump wavelength comprises selectively passing one pump wavelength from a plurality of pump wavelengths received. 43. The method of claim 28, wherein manipulating at least the intensity of the pump wavelength comprises controlling a drive current to a light source generating the pump wavelength to control the intensity of the pump wavelength. 44. The method of claim 28, further comprising:producing a pump beam; anddirecting the pump beam to a bandwidth adding mirror to generate a broadband pump spectrum;w herein the pump wavelength comprises at least a portion of the broadband pump spectrum. 45. The method of claim 28, wherein the gain medium comprises an optical fiber. 46. The method of claim 28, further comprising applying a gain flattening element to the multiple wavelength optical signal to reduce variations in amplitude as a function of wavelength in the multiple wavelength optical signal. 47. A Raman amplifier stage comprising:a pump assembly operable to generate a plurality of pump wavelengths for introduction to a Raman gain medium carrying a multiple wavelength optical signal, the plurality of pump wavelengths comprising a pump spectrum having a shape, the pump assembly comprising one or more light sources operable to generate the plurality of pump wavelengths at specified intensities by controlling a current supplied to the light source, wherein the pump assembly tailors the shape of the pump spectrum operable to be tailored to affect a desired shape of a gain curve for the multiple wavelength optical signal by controlling the current supplied to the light source; wherein the pump spectrum facilitates Raman amplification of at least a portion of the multiple wavelength signal over at least a portion of the gain medium, and wherein the shape of the gain curve for the multiple wavelength signal is determined at least in part by the shape of the pump spectrum. 48. The Raman amplifier stage of claim 47, wherein the shape of the pump spectrum is tailored by controlling the wavelengths of at least some of the pump wavelengths. 49. The Raman amplifier stage of claim 47, further comprising a wavelength selector operable to select one or more of the plurality of pump wavelengths for application to the gain medium. 50. The Raman amplifier stage of claim 47, wherein the pump spectrum comprises a plurality of peaks. 51. The Raman amplifier stage of claim 50, wherein the plurality of peaks comprise at least three (3) peaks. 52. The Raman amplifier stage of claim 50, wherein the at least two of the plurality of peaks are separated by a line width of at least one of the peaks at one half power of that peak. 53. The Raman amplifier stage of claim 50, wherein at least two of the peaks comprise different amplitudes. 54. The Raman amplifier stage of claim 50, wherein each of the peaks comprises an amplitude within ten (10) decibels of each of the others of the plurality of peaks. 55. The Raman amplifier stage of claim 50, wherein each peak resides at a different center wavelength. 56. The Raman amplifier stage of claim 50, wherein each of the plurality of peaks is spaced from all adjacent peaks by a substantially uniform wavelength spacing. 57. The Raman amplifier stage of claim 50, wherein a wavelength spacing between a first pair of adjacent peaks of the plurality of peaks is different than a wavelength spacing between a second pair of adjacent peaks of the plurality of peaks. 58. The Raman amplifier stage of claim 47, wherein the pump assembly comprises:a pump laser having an output port and producing a pump beam; anda bandwidth adding mirror connected to said output port to generate a broadened pump spectrum. 59. The Raman amplifier stage of claim 47, wherein the pump assembly comprises an array of laser diodes. 60. The Raman amplifier stage of claim 47, wherein the Raman gain medium comprises an optical fiber. 61. The Raman amplifier stage of claim 47, further comprising a gain flattening element coupled to the gain medium and operable to reduce variations in amplitude as a function of wavelength of the multiple wavelength optical signal output from the gain medium. 62. The Raman amplifier stage of claim 47, further comprising:an input port capable of receiving the multiple wavelength optical signal; andan output port capable of communicating the amplified multiple wavelength optical signal. 63. A method of controlling the shape of a gain curve of a Raman amplifier stage, comprising:receiving a multiple wavelength signal at a Raman gain medium of a Raman amplifier stage;generating a pump spectrum comprising a plurality of pump wavelengths; tailoring the shape of at least a portion of the pump spectrum to affect a desired shape of a gain curve for the multiple wavelength signal; andintroducing the pump spectrum to the gain medium to facilitate Raman amplification of at least a portion of the multiple wavelength signal over at least a portion of the gain medium, wherein the shape of the gain curve for the multiple wavelength signal is determined at least in part by the shape of the pump spectrum. 64. The method of claim 63, wherein tailoring the shape of the pump spectrum comprises selecting wavelengths of at least some of the plurality of pump wavelengths. 65. The method of claim 63, wherein tailoring the shape of the pump spectrum comprises selectively passing to the gain medium one or more pump wavelengths from a plurality of pump wavelengths received. 66. The method of claim 63, wherein the tailoring the shape of the pump spectrum comprises selecting the intensity of at least some of the plurality of pump wavelengths. 67. The method of claim 63, wherein the plurality of pump spectrum comprises a plurality of peaks. 68. The method of claim 67, wherein the plurality of peaks comprise at least three (3) peaks. 69. The method of claim 67, wherein the at least two of the plurality of peaks are separated by a line width of at least one of the peaks at one half power of that peak. 70. The method of claim 67, wherein at least two of the peaks comprise different amplitudes. 71. The method of claim 67, wherein each of the peaks comprises an amplitude within ten (10) decibels of each of the other of the plurality of peaks. 72. The method of claim 67, wherein each peak resides at a different center wavelength. 73. The method of claim 67, wherein each of the plurality of peaks is spaced from all adjacent peaks by a substantially uniform wavelength spacing. 74. The method of claim 67, wherein a wavelength spacing between a first pair of adjacent peaks of the plurality of peaks is different than a wavelength spacing between a second pair of adjacent peaks of the plurality of peaks. 75. The method of claim 63, further comprising:producing a pump beam; anddirecting the pump beam to a bandwidth adding mirror to generate a broadband pump spectrum;wherein the pump wavelength comprises at least a portion of the broadband pump spectrum. 76. The method of claim 63, wherein the gain medium comprises an optical fiber. 77. The method of claim 63, further comprising applying a gain flattening element to the multiple wavelength optical signal to reduce variations in amplitude as a function of wavelength in the multiple wavelength optical signal. 78. A Raman amplifier stage comprising:a Raman gain medium operable to receive a multiple wavelength optical signal;a pump assembly operable to generate at least one pump signal for introduction to the gain medium, the pump assembly comprising a wavelength selector operable to select a desired wavelength; anda coupler operable to introduce the at least one pump signal to the gain medium to facilitate Raman amplification of at least a portion of the multiple wavelength optical signal,wherein the wavelength selected by the wavelength selector is chosen to affect a desired shape of a gain curve associated with the multiple wavelength optical signal in the Raman amplifier stage. 79. A Raman amplifier stage comprising:a pump assembly operable to generate a plurality of pump wavelengths for introduction to a Raman gain medium carrying a multiple wavelength optical signal, the plurality of pump wavelengths comprising a pump spectrum having a shape, the pump assembly comprising a wavelength selector operable to select the plurality of pump wavelengths, wherein the wavelength selector tailors the shape of the pump spectrum to affect a desired shape of a gain curve for the multiple wavelength optical signal by selecting the plurality of pump wavel engths;wherein the pump spectrum facilitates Raman amplification of at least a portion of the multiple wavelength signal over at least a portion of the gain medium, and wherein the shape of the gain curve for the multiple wavelength signal is determined at least in part by the shape of the pump spectrum.