We have experimentally studied the propagation in free space and through focusing optics of subpicosecond half- and single-cycle terahertz pulses emitted by large-aperture emitters. The spatial transformations of the beams are connected to phase changes and effective frequency filtering and lead to spectacular changes in the pulse time profile. The experimental results are in excellent agreement with the predictions of a simple analytical model based on a Gaussian-beam approximation.
© 1999 Optical Society of America
Petr Kužel, Maxim A. Khazan, and Jan Kroupa, "Spatiotemporal transformations of ultrashort terahertz pulses," J. Opt. Soc. Am. B 16, 1795-1800 (1999)