Premium
Subpicosecond X‐ray diffraction study of laser‐induced disorder dynamics above the damage threshold of organic solids
Author(s) -
Rousse A.,
Rischel C.,
Uschmann I.,
Förster E.,
Albouy P. A.,
Geindre J. P.,
Audebert P.,
Gauthier J. C.,
Antonetti A.
Publication year - 1999
Publication title -
journal of applied crystallography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.429
H-Index - 162
ISSN - 1600-5767
DOI - 10.1107/s0021889899008870
Subject(s) - femtosecond , diffraction , laser , picosecond , excited state , ultrashort pulse , x ray crystallography , crystal (programming language) , plasma , materials science , wavelength , drop (telecommunication) , chemistry , atomic physics , optics , molecular physics , analytical chemistry (journal) , optoelectronics , physics , telecommunications , quantum mechanics , computer science , programming language , chromatography
Ultrafast disordering in Langmuir–Blodgett (LB) films and TlAP (thallium acid phthalate) crystals has been investigated by optical‐pump–X‐ray‐probe experiments using intense femtosecond laser pulses. A laser‐produced plasma X‐ray source at 7.12 Å wavelength is used to study atomic dynamics by subpicosecond time‐resolved X‐ray diffraction. It is found that a drop of the X‐ray diffracted intensity appears with time constants from below 600 fs up to a few tens of picoseconds in LB films optically excited at laser fluxes from 1.8 to 27 J cm −2 . This loss in the diffracted intensity is understood as a displacement of the diffracting atoms by ∼8 Å from their equilibrium position. The response of the TlAP crystal was significantly slower. The relation to the atomic structure of the materials is discussed.