Analysis of 160 Gb/s all-optical NRZ-to-RZ data format conversion using quantum-dot semiconductor optical amplifiers assisted Mach-Zehnder interferometer

A scheme of all-optical data format conversion from nonreturn-to-zero to return-to-zero is proposed using quantum-dot semiconductor optical amplifiers (QD SOAs) assisted Mach-Zehnder interferometer (MZI). The proposed scheme has the potential to operate at much larger bit rate ∼160 Gb/s, and the converted signal has a lower frequency chirp. 160 Gb/s all-optical format conversion is verified through numerical simulations, and the output contrast ratio and Q-factor are analyzed to evaluate the system performance. With properly selected parameters, the converted signal with a contrast ratio over 8 dB and a Q-factor over 8 can be achieved.