Eight-channel wavelength multiplexing with 200-GHz spacing using uncooled coaxial fiber Bragg grating external-cavity semiconductor laser module

As a low-cost light source for wavelength-division-multiplexing networks, the authors develop an uncooled coaxial fiber Bragg grating external-cavity semiconductor laser (FGL). To realize high-wavelength stability, an FGL structure is adopted, and to reduce the cost of light source itself, a coaxial pigtail module structure is selected. High-wavelength stabilities of 2 pm/mA and 12 pm/K against current and ambient temperature variation are realized. Using the FGLs, successive eight-channel wavelength multiplexing with 200-GHz spacing and with almost the same peak power is realized between -30/spl deg/C to 70/spl deg/C. For each channel, the wavelength difference from the corresponding ITU grid is only within /spl plusmn/0.1 nm at 25/spl deg/C.