title: Mid-infrared laser filaments in the atmosphere.
abstract: Filamentation of ultrashort laser pulses in the atmosphere offers unique opportunities for long-range transmission of high-power laser radiation and standoff detection. With the critical power of self-focusing scaling as the laser wavelength squared, the quest for longer-wavelength drivers, which would radically increase the peak power and, hence, the laser energy in a single filament, has been ongoing over two decades, during which time the available laser sources limited filamentation experiments in the atmosphere to the near-infrared and visible ranges. Here, we demonstrate filamentation of ultrashort mid-infrared pulses in the atmosphere for the first time. We show that, with the spectrum of a femtosecond laser driver centered at 3.9 μm, right at the edge of the atmospheric transmission window, radiation energies above 20 mJ and peak powers in excess of 200 GW can be transmitted through the atmosphere in a single filament. Our studies reveal unique properties of mid-infrared filaments, where the generation of powerful mid-infrared supercontinuum is accompanied by unusual scenarios of optical harmonic generation, giving rise to remarkably broad radiation spectra, stretching from the visible to the mid-infrared.
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia [3] Institute of Laser and Information Technologies, Russian Academy of Sciences, Shatura, Moscow Region, 140700 Russia.
authors: A V
authors: AV
authors: Mitrofanov
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
authors: A A
authors: AA
authors: Voronin
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
authors: D A
authors: DA
authors: Sidorov-Biryukov
authors: Photonics Institute, Vienna University of Technology, Gusshausstrasse 27-387, 1040 Vienna, Austria.
authors: A
authors: A
authors: Pugžlys
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
authors: E A
authors: EA
authors: Stepanov
authors: Photonics Institute, Vienna University of Technology, Gusshausstrasse 27-387, 1040 Vienna, Austria.
authors: G
authors: G
authors: Andriukaitis
authors: Photonics Institute, Vienna University of Technology, Gusshausstrasse 27-387, 1040 Vienna, Austria.
authors: T
authors: T
authors: Flöry
authors: Photonics Institute, Vienna University of Technology, Gusshausstrasse 27-387, 1040 Vienna, Austria.
authors: S
authors: S
authors: Ališauskas
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia.
authors: A B
authors: AB
authors: Fedotov
authors: Photonics Institute, Vienna University of Technology, Gusshausstrasse 27-387, 1040 Vienna, Austria.
authors: A
authors: A
authors: Baltuška
authors: 1] Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region, 143025 Russia [2] Physics Department, International Laser Center, M.V. Lomonosov Moscow State University, Moscow 119992, Russia [3] Department of Physics and Astronomy, Texas A&M University, College Station TX 77843, USA.
authors: A M
authors: AM
authors: Zheltikov