Real-time 200 Gb/s (4×56.25 Gb/s) PAM-4 transmission over 80 km SSMF using quantum-dot laser and silicon ring-modulator

Abstract

We report real-time 4×56.26-Gb/s DWDM PAM-4 transmission over 80-km SSMF with novel optical transmitter sub-assembly comprising multi-wavelength quantum-dot laser and silicon ring modulators. Pre-FEC BERs below 1E-4 are achieved after 80-km, allowing error-free operation with HD-FEC.