3D Model of Terahertz Photoconductive Antenna using COMSOL Multiphysics

This paper presents a 3D model of a photoconductive antenna (PCA) on semiconductor substrate. The simulations were conducted using the COMSOL Multiphysics package. The model considers the laser excitation and the carrier generation acceleration in the semiconductor layer. The computational work was achieved using the frequency-domain RF module and the semiconductor module. The results demonstrate that simulating the active area alone produces sufficient accuracy ~0.01 % in the RF module solution (solution of the electric and magnetic fields) and ~ 0.23% in the semiconductor solution (photo current solution). The reduction in the simulated area helps minimizing the required CPU time and memory requirement in the 3D model. The largest case in this study was simulated at the National XSEDE Supercomputing with ~0.3 billion unknowns and memory requirement of ~3.2TB in the RF module.