A spatio-temporal finite difference time domain simulation technique to estimate terahertz pulse profile of a photo-conductive antennae

Photoconductive Antennae have established itself as a cornerstone in the development of portable THz technology. The understanding of the complex dynamics of the carriers during the operation of the PCA is of utmost importance not only during the operation but also in further design evolution of the same. However practical design considerations are rarely incorporated into the theoretical simulations of Photoconductive Antennae. In this article, we propose the use of a Spatio- Temporal Finite Difference Time Domain modification of the existing simulation techniques to estimate THz pulse profiles. The article shows that the treatment of the instantaneous electrostatic forces and electron dynamics in a hypothetical 1-Dimensional semiconductor pathway used for the operation of a PCA can yield similar types of pulse profiles as obtained in experimental conditions. Also, the evolution of such a system in terms of dimensions (i.e. upto 3D) and incorporating other forces / physical effects mentioned may also lead to a more accurate simulation of a proposed structure.