THz Device Applications of Plasmons in Graphene

Abstract

In this review, we introduce terahertz (THz) emitters and detectors that utilize the hydrodynamic properties of two-dimensional plasmons in graphene and active plasmonic devices that utilize the interband population inversion and stimulated emission of THz photons enabled by the zero bandgap of graphene. Physical properties of two-dimensional plasmons and operation mechanisms of plasmonic emitters and detectors based on hydrodynamic plasma instability and nonlinearity, which have been studied for compound semiconductor heterostructures, are reviewed, and superiorities of graphene as a channel material are mentioned. The interband population inversion and THz stimulated emission specific to graphene are reviewed, and the active plasmonic waveguide as well as the plasmonic laser are introduced.