Optical Gaussian pulse source based on spectrum slicing and frequency chirp compression

• We generate a better seed pulse featuring shorter pulsewidth.
• The duty cycle can be further reduced by increasing the modulation index.
• 25-GHz 3-ps Gaussian pulse with an ER of 29 dB is achieved.
• The pulse source is also tunable over C band.
• Error-free 100-Gbit/s signal over 100-km transmission is performed.

An external-modulated optical Gaussian pulse generator based on optical filtering and chirp compression is proposed. The scheme works in linear regime using two phase modulators which does not require nonlinear compression and bias control. Theoretical and numerical analysis is first performed to elaborate the working principle and optimize the working condition of the pulse source. Using the analysis as a guideline, nearly chirp-free 25-GHz 3-ps Gaussian pulses are experimentally achieved over C band. The pulse source is further applied in 100-Gbit/s optical time-division multiplexing (OTDM) transmission system and the power penalty for 100-km transmission at a bit error rate (BER) of 10−9 is 0.6-dB, which demonstrates that the pulse generator is a simple, robust and practical pulse source for OTDM applications.