Graphene characterization using time-domain terahertz spectroscopy for plasmonic antenna design.

Grapheneu0027s ability to support surface plasmon polaritons (SPPs) is of particular interest in the design of nanoscale plasmonic antennas. Since a dielectric-conductor interface is required to excite and sustain SPPs, a negative dielectric function becomes a defining property for graphene. We use terahertz time-domain spectroscopy (THz-TDS) to determine the complex dielectric function of graphene based on the extracted complex conductivity. These optical properties help us ascertain if a graphene sample is capable of supporting plasmons, and the appropriate dimensions to define a resonant cavity that would act as an antenna in the THz range.