title: Optically controlled terahertz beam steering and imaging.
abstract: We propose a spatial modulator for terahertz waves based on light induced electron plasma in photo-active semiconductors. A two-dimensional array of computer controlled light is used to create free carries in bulk silicon, which results in a spatial modulation of the transmission at terahertz frequencies. This method not only exhibits a remarkable modulation depth over a broad frequency range but also allows for an optically controlled beam steering of terahertz waves by inducing virtual grating structures. In addition, we analyze the possibility of all-optically controlled terahertz imaging.
authors.affiliation: Fachbereich Physik, Philipps-Universität Marburg, Renthof 5, 35032, Marburg, Germany. stefan.busch@physik.uni‑marburg.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Busch
authors.forename: Benedikt
authors.initials: B
authors.lastname: Scherger
authors.forename: Maik
authors.initials: M
authors.lastname: Scheller
authors.forename: Martin
authors.initials: M
authors.lastname: Koch