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arXiv · 0908.2145

Steplike intensity threshold behavior of extreme ionization in laser-driven Xe clusters

T. Döppner·J. P. Müller·A. Przystawik·S. Göde·J. Tiggesbäumker·K. -H. Meiwes-Broer·C. Varin·L. Ramunno·T. Brabec·T. Fennel
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Abstract

The generation of highly charged Xe$^{q+}$ ions up to {$q=24$} is observed in Xe clusters embedded in helium nanodroplets and exposed to intense femtosecond laser pulses ($λ$=800 nm). Laser intensity resolved measurements show that the high-$q$ ion generation starts at an unexpectedly low threshold intensity of about {10$^{14}$ W/cm$^{2}$}. Above threshold, the Xe ion charge spectrum saturates quickly and changes only weakly for higher laser intensities. Good agreement between these observations and a molecular dynamics analysis allows us to identify the mechanisms responsible for the highly charged ion production and the surprising intensity threshold behavior of the ionization process.

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T. Döppner, J. P. Müller, A. Przystawik, S. Göde, J. Tiggesbäumker, K. -H. Meiwes-Broer, C. Varin, L. Ramunno, T. Brabec, T. Fennel. 2010-03-06. Steplike intensity threshold behavior of extreme ionization in laser-driven Xe clusters. https://doi.org/10.1103/physrevlett.105.053401

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