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arXiv · 1603.08659

Efficiency of Dopant-Induced Ignition of Helium Nanoplasmas

A. Heidenreich·B. Gruener·M. Rometsch·S. R. Krishnan·F. Stienkemeier·M. Mudrich
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Abstract

Helium nanodroplets irradiated by intense near-infrared laser pulses ignite and form highly ionized nanoplasmas even at laser intensities where helium is not directly ionized by the optical field, provided the droplets contain a few dopant atoms. We present a combined theoretical and experimental study of the He nanoplasma ignition dynamics for various dopant species. We find that the efficiency of dopants to ignite a nanoplasma in helium droplets strongly varies and mostly depends on (i) the pick-up process, (ii) the number of free electrons each dopant donates upon ionization, and remarkably, (iii) by the hitherto unexplored effect of the dopant location in or on the droplet.

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A. Heidenreich, B. Gruener, M. Rometsch, S. R. Krishnan, F. Stienkemeier, M. Mudrich. 2016-03-29. Efficiency of Dopant-Induced Ignition of Helium Nanoplasmas. https://doi.org/10.1088/1367-2630%2F18%2F7%2F073046

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