Imec, the Belgian micro and nanoelectronics research center, together with Ghent University, demonstrated the world's first integrated graphene optical electro-absorption modulator (EAM) capable of 10Gb/s modulation speed in a recent IEEE International Electron Devices Meeting (IEDM 2014).

The modulator combines low insertion loss, low drive voltage, high thermal stability, broadband operation and compact footprint. Such integrated can be highly beneficial for future chip-level optical interconnects.

This graphene-silicon EAM consists of a 50µm long graphene-oxide-silicon capacitor structure, on top of a planarized silicon-on-insulator (SOI) rib waveguide. It allows for high-quality optical modulation, at bit rates up to 10Gb/s. No significant changes in performance were observed for temperatures in the range of 20-49°C, implying a robust athermal operation. The scientists say that this graphene-silicon EAM outperforms state-of-the-art SiGe EAMs on thermal robustness and optical bandwidth specifications.