Study of The Spectral Response of A Terahertz Antenna Detector When The Surrounding Dielectric Changes

Abstract

In this paper, the surface wave theory is used to study the spectral response of a terahertz antenna detector when the surrounding dielectric material is changed. As simulation shows, surrounding dielectrics affect the velocity of the current pulse propagation on electrodes. The propagation spectrum of the bow-tie and the dipole antenna on the LT-GaAs substrate is simulated through the FDTD method using the CST software. The current pulse generated in the antenna gap is also calculated with the Drude model. It is found that the type and the thickness of surrounding dielectrics affect the spectral responses of detector antennas as far as the peaks of the corresponding spectra shift down to one terahertz.