Article

Revival of femtosecond laser plasma filaments in air by a nanosecond laser

Teramobile Project, Laboratoire d'Optique Appliquée, Ecole Nationale Supérieure des Techniques Avancées-Ecole Polytechnique, CNRS UMR 7639, F-91761 Palaiseau Cedex, France.
Optics Express (Impact Factor: 3.49). 08/2009; 17(14):11450-6. DOI: 10.1364/OE.17.011450
Source: PubMed

ABSTRACT Short lived plasma channels generated through filamentation of femtosecond laser pulses in air can be revived after several milliseconds by a delayed nanosecond pulse. Electrons initially ionized from oxygen molecules and subsequently captured by neutral oxygen molecules provide the long-lived reservoir of low affinity allowing this process. A Bessel-like nanosecond-duration laser beam can easily detach these weakly bound electrons and multiply them in an avalanche process. We have experimentally demonstrated such revivals over a channel length of 50 cm by focusing the nanosecond laser with an axicon.

Download full-text

Full-text

Available from: Aurélien Houard, Sep 02, 2015
0 Followers
 · 
185 Views
 · 
69 Downloads
  • [Show abstract] [Hide abstract]
    ABSTRACT: We study the interaction of two parallel-launched femtosecond filaments at their fundamental-wave and second-harmonic frequencies in air. Besides the Kerr effect within the pulse duration, the impulsive alignment of the diatomic molecules in the fundamental-wave filament leads to controllable and field-free achievable attraction, fusion, or repulsion of the second-harmonic filament. The molecular-alignment-assisted filament interaction is further confirmed by the fluorescence intensity variation and spectral modulation of the second-harmonic filament at various molecular alignment revivals.
    Optics Letters 10/2009; 34(20):3211-3. DOI:10.1364/OL.34.003211 · 3.18 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A detailed model of plasma dynamics, which self-consistently integrates plasma-kinetic, Navier–Stokes, electron heat conduction, and electron-vibration energy transfer equations, is used to quantify the limitations on the lifetime of microwave plasma waveguides induced in the atmosphere through filamentation with high-intensity ultrashort laser pulses further sustained by long laser pulses. We demonstrate that a near-infrared or midinfrared laser pulse can tailor plasma decay in the wake of a filament, efficiently suppressing, through electron temperature increase, the attachment of electrons to neutral species and dissociative recombination, thus substantially increasing the plasma-guide lifetime and facilitating long-distance transmission of microwaves.
    Journal of Applied Physics 08/2010; 108(3):033113-033113-8. DOI:10.1063/1.3457150 · 2.19 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We present a comprehensive model of plasma dynamics that enables a detailed understanding of the ways the air plasma induced in the atmosphere in the wake of a laser-induced filament can be controlled by an additional laser pulse. Our model self-consistently integrates plasma-kinetic, Navier−Stokes, electron heat conduction, and electron−vibration energy transfer equations, serving to reveal laser−plasma interaction regimes where the plasma lifetime can be substantially increased through an efficient control over plasma temperature, as well as suppression of attachment and recombination processes. The model is used to quantify the limitations on the length of uniform laser-filament heating due to the self-defocusing of laser radiation by the radial profile of electron density. The envisaged applications include sustaining plasma guides for long-distance transmission of microwaves, standoff detection of impurities and potentially hazardous agents, as well as lightning control and protection.
    Physics of Plasmas 06/2011; 18(6):063509-063509-9. DOI:10.1063/1.3601764 · 2.25 Impact Factor
Show more