Introduction to the issue on graphene optoelectronics

This issue contains 17 papers, including seven invited and ten contributed papers, authored by some of the leading graphene optoelectronics research groups in the world. The papers in this special issue cover the broad scope of research representative of this growing field. Four areas are highlighted: 1) Graphene Plasmonics and Optoelectronics: These papers discuss optical excitations of graphene, including interband, intraband, and plasmon excitations.Mechanisms by which photons can be converted to an electrical current in graphene are reviewed. Device applications as photodetector, modulator, and interconnect are presented. Also, latest achievements in graphene-based terahertz photonics are reviewed. 2) Integration of Graphene Into Nanophotonic Devices: Nanophotonic devices can strongly enhance the interaction of light with graphene. These papers present concepts for waveguide- and cavity-coupled graphene devices and applications as optical modulators, photodetectors, and polarizers. 3) Graphene for Transparent Conducting Electrodes: These papers discuss the potential of graphene to replace indium tin oxide as transparent electrode in large-scale optoelectronics devices and present laser-based methods for the reduction of graphene oxide films to produce transparent graphene layers with low sheet resistance. 4) Nonlinear Optical Phenomena in Graphene: These papers discuss nonlinear optical phenomena in graphene, such as optical four-wave mixing and saturable absorption. The application of graphene for generating Q-switched and mode-locked pulses in a laser, polarization-dependent saturable absorbers, low power switching, signal regeneration and parametric conversion in graphene-nanophotonic devices are presented.