We include screening of the bias field by the space charge induced by carrier transport and by the generated terahertz radiation in a model describing the far-field electromagnetic radiation from a large-aperture biased photoconductor triggered by an ultrashort optical pulse. At high fluences, space-charge screening is shown to produce bipolar terahertz waveforms. However, the dominant saturation mechanism is screening of the bias field by the radiated terahertz field.
© 1996 Optical Society of America
Original Manuscript: January 16, 1996
Published: July 15, 1996
G. Rodriguez and A. J. Taylor, "Screening of the bias field in terahertz generation from photoconductors," Opt. Lett. 21, 1046-1048 (1996)