Error-Free Data Transmission Through Fast Broadband All-Optical Modulation In Graphene-Silicon Optoelectronics

Ultrafast third order nonlinearity in silicon photonics is promising for all-optical signal processing beyond 100 Gbit/s. However, the coexistence of slower dynamical responses, such as mesoscopic Drude free-carrier plasma or thermal nonlinearities, degrades high-speed signal integrity. Here, we introduce atomic-layer graphene onto the silicon nanophotonic platform to leverage its unique nondegenerate two-photon absorption and ultrafast carrier dynamics, demonstrating broadband and fast bitrate transmission through cross-absorption modulation. Multichannel error-free optical transmission across telecommunication C- and L-bands is demonstrated with 10(-12) bit-error rates at a data transmission rate of 1 Gbps. The bandwidth of the hybrid silicon-graphene structure is demonstrated at least up to 25GHz. The broadband cross-absorption modulation over 640nm in graphene-silicon optoelectronics provides a promising scalable material platform for high-speed all-optical signal processing.