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arXiv · 0902.2635

Laser-driven nanoplasmas in doped helium droplets: Local ignition and anisotropic expansion

Alexey Mikaberidze·Ulf Saalmann·Jan M. Rost
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Abstract

Doping a helium nanodroplet with a tiny xenon cluster of a few atoms only, sparks complete ionization of the droplet at laser intensities below the ionization threshold of helium atoms. As a result, the intrinsically inert and transparent droplet turns into a fast and strong absorber of infrared light. Microscopic calculations reveal a two-step mechanism to be responsible for the dramatic change: Avalanche-like ionization of the helium atoms on a femtosecond time scale, driven by field ionization due to the quickly charged xenon core is followed by resonant absorption enabled by an unusual cigar-shaped nanoplasma within the droplet.

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Alexey Mikaberidze, Ulf Saalmann, Jan M. Rost. 2009-02-16. Laser-driven nanoplasmas in doped helium droplets: Local ignition and anisotropic expansion. https://doi.org/10.1103/physrevlett.102.128102

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