Oscillation wavelength of fiber Bragg grating semiconductor lasers
Based on the physical fact that a laser containing a gain medium with homogenous line broadening oscillates at the wavelength which requires the smallest threshold gain due to the mode competition effect, after taking into account the wavelength-depended reflectivity distribution profile of a fiber Bragg grating, the oscillation wavelength λ
l of fiber Bragg grating semiconductor lasers has been investigated theoretically. The results show that the laser oscillation wavelength λ
B is not fixed at the Bragg reflection wavelength λ
l of fiber Bragg grating, and the offset between λ
B and λ
l depends on the reflectivity distribution profile of fiber Bragg grating and the gain profile of semiconductor gain medium.