A wavelength selective light source is disclosed. The wavelength selective light source comprises a broadband light source producing light having a plurality of wavelengths and a demultiplexer that receives the light and separates at least one of the plurality of wavelengths from said light. Further, a multiplexer is included for coupling the at least one of said plurality of wavelengths into an output waveguide. Finally, a semiconductor optical amplifier is provided that receives the at least one of the plurality of wavelengths from the output waveguide and amplifies the at least one of the plurality of wavelengths.