title: Kilometer-range nonlinear propagation of femtosecond laser pulses.
abstract: Ultrashort, high-power laser pulses propagating vertically in the atmosphere have been observed over more than 20 km using an imaging 2-m astronomical telescope. This direct observation in several wavelength bands shows indications for filament formation at distances as far as 2 km in the atmosphere. Moreover, the beam divergence at 5 km altitude is smaller than expected, bearing evidence for whole-beam parallelization about the nonlinear focus. We discuss implications for white-light Lidar applications.
authors.affiliation: Teramobile, Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany.
authors.forename: Miguel
authors.initials: M
authors.lastname: Rodriguez
authors.forename: Riad
authors.initials: R
authors.lastname: Bourayou
authors.forename: Guillaume
authors.initials: G
authors.lastname: Méjean
authors.forename: Jérôme
authors.initials: J
authors.lastname: Kasparian
authors.forename: Jin
authors.initials: J
authors.lastname: Yu
authors.forename: Estelle
authors.initials: E
authors.lastname: Salmon
authors.forename: Alexander
authors.initials: A
authors.lastname: Scholz
authors.forename: Bringfried
authors.initials: B
authors.lastname: Stecklum
authors.forename: Jochen
authors.initials: J
authors.lastname: Eislöffel
authors.forename: Uwe
authors.initials: U
authors.lastname: Laux
authors.forename: Artie P
authors.initials: AP
authors.lastname: Hatzes
authors.forename: Roland
authors.initials: R
authors.lastname: Sauerbrey
authors.forename: Ludger
authors.initials: L
authors.lastname: Wöste
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Wolf