Period-Doubling in 10 GHz Gain-Switched DFB Laser Diode

The distinct period doubling behaviour in a 10 GHz gain-switched （GS） DFB laser is experimentally investigated in frequency domain and in time domain. The period doubling occurs as the frequency of the rf driving signal is close to or higher than the-3 dB cutoff frequency of the DFB laser diode, and the amplitude of the rf driving signal required to achieve period doubling increases linearly with the increasing bias current of the laser diode.     

Optical Pulse Generation with Self-Cascaded Electroabsorption Modulator

A novel scheme for pulse generation with a self-cascaded electroabsorption modulator is presented and experimentally demonstrated at 10 GHz. In the case of optimal tuning of time delay in the fibre loop, the improvement of 50% on pulsewidth with improved extinction ratio is obtained and the narrowest pulse generated with this method is about 11ps.