Optical Pre-Emphasis by Cascaded Graphene Electro Absorption Modulators

A simple optical circuit made by a cascade of two graphene-on-silicon EAMs of different length is used for the optical pre-emphasis of 10 Gb/s non-return-to-zero (NRZ) signals by delay-inverse-weight compensation. Transmission up to 100 km on single mode fiber (SMF) without dispersion compensation is reported, showing also the large performance advantage (6 dB in back-to back, around 5 dB in transmission) in respect of the conventional single EAM transmitter configuration.