title: Probing hot and dense laser-induced plasmas with ultrafast XUV pulses.
abstract: In this Letter, we demonstrate the instantaneous creation of a hot solid-density plasma generated by focusing an intense femtosecond, high temporal contrast laser on an ultrathin foil (100 nm) in the 10(18) W/cm2 intensity range. The use of high-order harmonics generated in a gas jet, providing a probe beam of sufficiently short wavelengths to penetrate such a medium, enables the study of the dynamics of this plasma on the 100 fs time scale. The comparison of the transmission of two successive harmonics permits us to determine the electronic density and the temperature with accuracies better than 15%, never achieved up to this date in the regime of laser pulses at relativistic intensity.
authors.affiliation: Service des Photons, Atomes et Molécules, Commissariat à l'Energie Atomique, DSM/DRECAM, CEN Saclay, 91191 Gif sur Yvette, France.
authors.forename: S
authors.initials: S
authors.lastname: Dobosz
authors.forename: G
authors.initials: G
authors.lastname: Doumy
authors.forename: H
authors.initials: H
authors.lastname: Stabile
authors.forename: P
authors.initials: P
authors.lastname: D'Oliveira
authors.forename: P
authors.initials: P
authors.lastname: Monot
authors.forename: F
authors.initials: F
authors.lastname: Réau
authors.forename: S
authors.initials: S
authors.lastname: Hüller
authors.forename: Ph
authors.initials: P
authors.lastname: Martin