Resonant frequency tuning and transmission enhancement of terahertz plasmonic antenna by dielectric engineering

We report on a technique for tuning a resonant frequency and enhancing transmission of a bull's eye (BE) plasmonic antenna by forming dielectric materials on a sub-wavelength aperture. We observed that the use of the dielectric material shifted the peak frequency of terahertz (THz) transmission through the aperture and also enhanced the transmittance. These results indicate the usefulness of dielectric engineering for THz plasmon and potential applications such as a tunable plasmonic antenna and a dielectric molecular sensor.