4×56-GBaud PAM-4 SDM Transmission over 5.9-km 125-µm-Cladding MCF using III-V-on-Si DMLs

We demonstrate 4×56-GBaud PAM-4 signals over 125-μm-cladding, 4-core fiber by simultaneous, direct modulation of four 1.3-pm membrane III-V-on-silicon lasers, each requiring <; 25-mWatts (@12 mA). A reach extension of ~15× is achieved compared to previous works.