Frequency chirp compensation of directly modulated DBR laser

We propose a model to analyze the frequency chirp of directly modulated distributed Bragg reflector (DBR) laser by evaluating the carrier dynamics in DBR. Due to the opposite sign of chirp in the gain and phase sections, the chirp compensation is achieved by injecting simultaneously injecting the data signals into both of the phase and gain sections in DBR laser. The simulation shows that, the overall chirp can be fully compensated, while the residual chirp at the rising and falling edges is only ~2 GHz. Moreover, the corresponding spectrum linewidth is significantly compressed after effective chirp compensation.