Reduction of frequency chirping and dynamic linewidth in high-speed directly modulated semiconductor lasers by injection locking

We report the reduction of frequency chirping and dynamic spectral linewidth in high-speed directly modulated semiconductor lasers, by external injection from a CW single-mode laser. Reduction by more than a factor of 2 in chirped line-width was obtained in a GaAlAs laser modulated with a 1 GHz, 100 Ps current pulses.