Deutsche Tagung f ¨ur Forschung mit ... - SNI-Portal

Materie unter extremen Bedingungen Poster: Do., 13:00–15:30 D-P361
Ultrafast scattering from clusters with intense soft x-ray radiation from the
FLASH FEL
Christoph Bostedt 1 , Ekatarina Eremina 1 , Heiko Thomas 1 , Matthias
Hoener 1 , Thomas Möller 1 , Hubertus Wabnitz 2 , Marion Kuhlmann 2 , Elke
Plönjes 2 , Rubens de Castro 2 , Tim Laarmann 3
1 Technische Universität Berlin – 2 Deutsches Elektronensynchrotron DESY Hamburg
– 3 Max Born Institut Berlin
The interaction of rare gas clusters with intense vacuum ultraviolett radiation from
the DESY FEL operating at 100 nm wavelength has yielded many surprising results.
For rare gas clusters unexpected high energy absorption was measured and thermionic
electron emission was observed. Already at 10 13 W/cm 2 the clusters completely disintegrated
in a coulomb explosion. These results indicate that for cluster in intense
laser fields down to 100 nm very efficient energy absorption mechanisms exist. From
a theoretical point of view new explanations for the observed energy absorption were
suggested, including atomic corrections to the inverse Bremsstrahlung potentials or
high intermediate charge states in the cluster.
In fall 2005 the FLASH FEL source (DESY VUV-FEL) became operational, currently
producing intense soft x-ray radiation with 32 nm wavelength and power densities of up
to 10 14 W/cm 2 . In the talk first results of the laser cluster interaction at this reduced
wavelength will be presented. The data show less efficient energy absorption from the
laser field and no thermionic electrons. At this reduced wavelength scattering experiments
at nanoparticles become feasible. We show first ultrafast single shot scattering
data from large clusters. The results indicate that the particles stay in tact during
exposure.