title: Ionization Avalanching in Clusters Ignited by Extreme-Ultraviolet Driven Seed Electrons.
abstract: We study the ionization dynamics of Ar clusters exposed to ultrashort near-infrared (NIR) laser pulses for intensities well below the threshold at which tunnel ionization ignites nanoplasma formation. We find that the emission of highly charged ions up to Ar^{8+} can be switched on with unit contrast by generating only a few seed electrons with an ultrashort extreme-ultraviolet (XUV) pulse prior to the NIR field. Molecular dynamics simulations can explain the experimental observations and predict a generic scenario where efficient heating via inverse bremsstrahlung and NIR avalanching is followed by resonant collective nanoplasma heating. The temporally and spatially well-controlled injection of the XUV seed electrons opens new routes for controlling avalanching and heating phenomena in nanostructures and solids, with implications for both fundamental and applied laser-matter science.
authors: Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.|Department of Physics, Imperial College London, South Kensington Campus, SW7 2AZ London, United Kingdom.
authors: Bernd
authors: B
authors: Schütte
authors: Institute of Physics, University of Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany.
authors: Mathias
authors: M
authors: Arbeiter
authors: Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.
authors: Alexandre
authors: A
authors: Mermillod-Blondin
authors: Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.
authors: Marc J J
authors: MJ
authors: Vrakking
authors: Max-Born-Institut, Max-Born-Straße 2A, 12489 Berlin, Germany.
authors: Arnaud
authors: A
authors: Rouzée
authors: Institute of Physics, University of Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany.
authors: Thomas
authors: T
authors: Fennel