Graphene for Terahertz Applications
The optoelectronic properties of graphene are being explored for possible use in plasmonics and metamaterials at terahertz frequencies. Graphene is a one-atom-thick sheet of carbon atoms arranged in a honeycomb lattice. First obtained by exfoliation of graphite in 2004 (1), graphene has since evolved into a thriving research topic because of its attractive mechanical, thermal, and electrical properties (2–4), particularly the exceptionally high electron mobility. Such properties promise to revolutionize many applications (2–4), ranging from solar cells and light-emitting devices to touch screens, photodetectors (4), microwave transistors (5), and ultrafast lasers (6). We discuss here a number of special qualities of graphene that also make it desirable for devices manipulating terahertz waves.