Improving Efficiency of Terahertz Photoconductive Antenna Using Dielectric Nano-Layer Encapsulation

Due to the low optical-to-THz conversion efficiencies, applications of photoconductive antennas are limited in current scenario. In this paper, we report up to an order of enhancement in THz emission efficiency from conventional PCAs by coating a nano-layer of dielectric (TiO
₂
) on the active area between the electrodes of a Semi-Insulating GaAs (SI-GaAs) based device. Effect of different thicknesses of the TiO
₂
layer on THz power enhancement with different applied optical power and bias voltages were studied. Simulations in COMSOL Multiphysics
^®
(RF and semi-conductor modules) were performed to validate the enhancement in the efficiency of the PCA due to TiO
₂
layer coating.