Simple method for calculating the propagation of terahertz radiation in experimental geometries

A formalism based on plane-wave decomposition is applied to the linear propagation of terahertz pulses in experimental geometries. The approach is general and is not restricted to any particular polarization (or current) source. Near- and far-field expressions easily amenable to numerical computation are obtained for the temporal profiles and spectra of terahertz pulses in layered structures, as often encountered in experiments. The effects of polarization and angle-dependent multiple reflection and transmission, as well as of material dispersion, are included. Examples of optical rectification in GaAs and ZnTe are presented to illustrate the simplicity of the method and are compared with experiments. The numerical evaluation of the expressions for the terahertz electric field in practical experimental geometries is straightforward. (C) 2003 Optical Society of America.