Time-domain numerical modeling of THz receivers based on photoconductive antennas

Abstract

We present here a simulator that solves the main semiconductor charge and transport equations coupled to Maxwell equations to study receivers based on photoconductive antennas (R-PCAs). Making use of this tool we were able to correctly characterize the operation of these antennas. In doing so, we compared simulations with the results of the semi-empirical expression ITHz(t) ∝ σc(t) ∗ ETHz(t) employed to evaluate the detected photo-current by means of the convolution between the photoconductivity in the receiver and the electric field linked to the emitter antenna. We were able to accurately reproduce experimental data with our simulation tool. These kind of tools are essential to model photoconductive antennas, a fundamental step needed for the development of terahertz time domain spectroscopy (THz-TDS) applications based on PCAs.