title: 3D numerical simulations of THz generation by two-color laser filaments.
abstract: Terahertz (THz) radiation produced by the filamentation of two-color pulses over long distances in argon is numerically investigated using a comprehensive model in full space-time-resolved geometry. We show that the dominant physical mechanism for THz generation in the filamentation regime at clamping intensity is based on quasi-dc plasma currents. The calculated THz spectra for different pump pulse energies and pulse durations are in agreement with previously reported experimental observations. For the same pulse parameters, near-infrared pump pulses at 2  μm are shown to generate a more than 1 order of magnitude greater THz yield than pumps centered at 800 nm.
authors.affiliation: CEA-DAM, DIF, 91297 Arpajon, France.
authors.forename: Luc
authors.initials: L
authors.lastname: Bergé
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany and Institute of Condensed Matter Theory and Optics, Friedrich Schiller University, 07743 Jena, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Skupin
authors.affiliation: CEA-DAM, DIF, 91297 Arpajon, France and Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Köhler
authors.affiliation: Weierstrass-Institut für Angewandte Analysis und Stochastik, 10117 Berlin, Germany.
authors.forename: Ihar
authors.initials: I
authors.lastname: Babushkin
authors.affiliation: Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, 12489 Berlin, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Herrmann