title: Screening of the bias field in terahertz generation from photoconductors.
abstract: 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 f luences, 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.
authors.forename: G
authors.initials: G
authors.lastname: Rodriguez
authors.forename: A J
authors.initials: AJ
authors.lastname: Taylor