Effects of pulse duration on self-focusing of ultra-short lasers in underdense plasmas

Jérôme Faure 1 Victor Malka 1 J.R. Marques 1 P.-G. David 1 François Amiranoff 1 Kim Ta Phuoc 2 Antoine Rousse 2
1 LULI - Laboratoire pour l'utilisation des lasers intenses
2 LOA - Laboratoire d'optique appliquée
Abstract : An experiment investigating laser self-focusing in underdense plasmas is presented. It was shown experimentally that the critical power for relativistic self-focusing Pc is not the only relevant parameter, in particular when the laser pulse duration is comparable to plasma particle motion times: ωp−1 for electrons and ωpi−1 for ions. Using time resolved shadowgraphy, it was demonstrated that: (i) a pulse does not relativistically self-focus if its duration is too short compared to ωp−1, even in the case where the power is greater than Pc. This is due to defocusing by the longitudinal wake which is generated by the laser pulse itself. (ii) For pulses longer than ωpi−1, self-focusing can occur even for powers lower than Pc. This is due to the radial expansion of ions, creating a channel whose effect combines with relativistic focusing and helps the pulse to self-focus.
Keywords : plasma light propagation time resolved spectra plasma diagnostics relativistic plasmas high-speed optical techniques optical self-focusing
Document type :
Journal articles
Complete list of metadatas
https://hal-polytechnique.archives-ouvertes.fr/hal-00572533
Contributor : Thuy Le <>
Submitted on : Tuesday, March 1, 2011 - 4:45:03 PM
Last modification on : Tuesday, January 14, 2020 - 5:22:03 PM

Identifiers

Collections

UPMC | CNRS | X-LOA | X-LULI | X | CEA | DSM-IRAMIS | PARISTECH | ENSTA_LOA | ENSTA | CEA-DRF | X-DEP-PHYS | DAM | SORBONNE-UNIVERSITE | SU-SCIENCES

Citation

Jérôme Faure, Victor Malka, J.R. Marques, P.-G. David, François Amiranoff, et al.. Effects of pulse duration on self-focusing of ultra-short lasers in underdense plasmas. Physics of Plasmas, American Institute of Physics, 2002, 9 (3), pp.756. ⟨10.1063/1.1447556⟩. ⟨hal-00572533⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

357

Contact

Informations

CCSD