Decay of cystalline order and equilibration during the solid-to-plasma transition induced by 20-fs microfocused 92-eV free-electron-laser pulses

0362892 - FZÚ 2012 RIV US eng J - Journal Article
Galtier, E. - Rosmej, F.B. - Dzelzainis, T. - Riley, D. - Khattak, F.Y. - Heimann, P. - Lee, R. W. - Nelson, A.J. - Vinko, S.M. - Whitcher, T. - Wark, J. S. - Tschentscher, T. - Toleikis, S. - Fäustlin, R.R. - Sobierajski, R. - Jurek, M. - Juha, Libor - Chalupský, Jaromír - Hájková, Věra - Kozlová, Michaela - Krzywinski, J. - Nagler, B.
Decay of cystalline order and equilibration during the solid-to-plasma transition induced by 20-fs microfocused 92-eV free-electron-laser pulses.
Physical Review Letters. Roč. 106, č. 16 (2011), "164801-1"-"164801-4". ISSN 0031-9007. E-ISSN 1079-7114
R&D Projects: GA ČR GAP208/10/2302; GA MŠMT LA08024; GA AV ČR IAAX00100903; GA MŠMT(CZ) ME10046
Institutional research plan: CEZ:AV0Z10100523
Keywords : X-ray lasers * free-electron lasers * X-ray emission spectroscopy
Subject RIV: BH - Optics, Masers, Lasers
Impact factor: 7.370, year: 2011

We have studied a solid-to-plasma transition by irradiating Al foils with the FLASH free electron laser at intensities up to 10¹⁶ W/cm². Intense XUV self-emission shows spectral features that are consistent with emission from regions of high density, which go beyond single inner-shell photoionization of solids. Characteristic features of intrashell transitions allowed us to identify Auger heating of the electrons in the conduction band occurring immediately after the absorption of the XUV laser energy as the dominant mechanism. A simple model of a multicharge state inverse Auger effect is proposed to explain the target emission when the conduction band at solid density becomes more atomiclike as energy is transferred from the electrons to the ions. This allows one to determine, independent of plasma simulations, the electron temperature and density just after the decay of crystalline order and to characterize the early time evolution.
Permanent Link: http://hdl.handle.net/11104/0199067