Ionization dynamics in expanding clusters studied by XUV pump-probe spectroscopy

Krikunova M, Adolph M, Gorkhover T, Rupp D, Schorb S, Bostedt C, Roling S, Siemer B, Mitzner R, Zacharias H, Möller T

Research article (journal)

Abstract

The expansion and disintegration dynamics of xenon clusters initiated by the ionization with femtosecond soft x-ray extreme ultraviolet (XUV) pulses were studied with pump–probe spectroscopy using the autocorrelator setup of the Free-Electron LASer in Hamburg (FLASH) facility. The ionization by the first XUV pulse of 92eV photon energy (8 × 1012 W cm−2) leads to the generation of a large number of quasi-free electrons trapped by the space charge of the cluster ions. A temporally delayed, more intense probe (4 × 1013 W cm−2) pulse substantially increases a population of nanoplasma electrons providing a way of probing plasma states in the expanding cluster by tracing the average charge of fragment ions. The results of the study reveal a timescale for cluster expansion and disintegration, which depends essentially on the initial cluster size. The average charge state of fragment ions, and thus the cluster plasma changes significantly on a timescale of 1–3 ps.

Details zur Publikation

Pages: 6
Release year: 2012
Language in which the publication is written: English
Link to the full text: http://www.scopus.com/inward/record.url?partnerID=yv4JPVwI&eid=2-s2.0-84860830743&md5=008e108610fd60242687cc4d12257b6e