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

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.

4 pages, 4 figures

References in corpus (3)

• Spectroscopy and dynamics in helium nanodroplets
• Ionization of clusters in intense laser pulses through collective electron dynamics
• Energy absorption of xenon clusters in helium nanodroplets under strong laser pulses

Cited by in corpus (1)

• Photoionizaton of Pure and Doped Helium Nanodroplets