Numerical analysis of negative chirp operation in hybrid modulation semiconductor lasers

Abstract

The negative chirp operation of a hybrid modulation laser diode (HMLD) was numerically analyzed during operation with 25-Gbit/s non-return-to-zero (NRZ) dynamic signals. We confirmed that the dispersion tolerance of the 25-Gbit/s optical signal generated from the HMLD could be increased dramatically by introducing time delay to the modulation signals applied to the gain and intra-cavity loss modulation sections. These results suggest a unique approach for dispersion-tolerant directly modulated semiconductor lasers.