▎ 摘　　要

In this letter, we demonstrate that a graphene monolayer, over which three metallic electrodes forming a coplanar waveguide are patterned, acts as a frequency multiplier and generates frequencies at least up to 40 GHz. These results show that monolayer graphene is a natural frequency multiplier. (C) 2010 American Institute of Physics. [doi:10.1063/1.3483872]