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: 3.53). 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.

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