The Internet traffic that sustains our global society and economy is growing exponentially. Yet, the energy requirements for providing this bandwidth can no longer be ignored and will continue to increase with the amounts of exchanged data. The cost, size, and energy consumption of the present electronic equipment that manages these massive data flows across the network calls for the development of disruptive routing technologies. While the use of light has proved to be the most effective way to carry data over long distances in optical fibres, tasks such as data treatment or routing are performed in electronic routers, creating bottlenecks. More energy-efficient and compact methods are needed. One promising solution is the development of all-optical technologies in which the optical information would be directly processed across the network via another optical signal, i.e. without being converted into electrical signals. Such technology could efficiently complement electronic routers, and requires the development of novel platforms, in which the light–matter interaction is dramatically increased with respect to that in fibres. This implies an appropriate choice of materials and geometries to efficiently manipulate high-speed optical signals in compact and integrated chips. GRAPHICS aims at developing such devices based on graphene/ semiconductor hybrid integration and nanophotonic concepts that promote light-matter interaction.
Ideally, the developed technology should be compatible with CMOS processing and architectures, for enabling the convergence of optics and microelectronics. Computer chips meet with severe difficulties to keep up with increasing processing speed performance while maintaining low power consumption. Microelectronics would thus equally benefit from the development of inter- and intra-chip optical interconnects, where the advantages of optics (high transfer speed, high data-handling capacity) are brought down to the chip level.
GRAPHICS aims to create novel graphene/ semiconductor hybrid platforms, beyond silicon photonics, for the generation, processing, and manipulation of fast optical signals on-chip at Telecom wavelengths. Our research program focuses on two main classes of nonlinear optical devices: (1) integrated pulsed III-V/ Si microlasers capable of generating short optical pulses on a chip, and (2) all-optical signal processing devices using light to control light in a fast and efficient manner. These devices rely on two distinct nonlinear features of graphene, i.e. its saturable absorption and its nonlinear Kerr response. In addition, the capability of electrically tuning graphene optical properties can enable the creation of reconfigurable intelligent optical devices. The resulting architectures will underpin a variety of applications related to telecommunications, datacom, and inter-and intra-chip optical communications.
