Open AccessSpeckle correlation as a monitor of X‐ray free‐electron laser induced crystal lattice deformation
Author(s) -
Plumley Rajan,
Sun Yanwen,
Teitelbaum Samuel,
Song Sanghoon,
Sato Takahiro,
Chollet Matthieu,
Nelson Silke,
Wang Nan,
Sun Peihao,
Robert Aymeric,
Fuoss Paul,
Sutton Mark,
Zhu Diling
Publication year - 2020
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577520011509
Subject(s) - free electron laser , laser , optics , advanced photon source , fluence , physics , speckle pattern , ultrashort pulse , monochromatic color , scattering , diffraction , bragg's law , lattice (music) , particle accelerator , beam (structure) , acoustics
X‐ray free‐electron lasers (X‐FELs) present new opportunities to study ultrafast lattice dynamics in complex materials. While the unprecedented source brilliance enables high fidelity measurement of structural dynamics, it also raises experimental challenges related to the understanding and control of beam‐induced irreversible structural changes in samples that can ultimately impact the interpretation of experimental results. This is also important for designing reliable high performance X‐ray optical components. In this work, X‐FEL beam‐induced lattice alterations are investigated by measuring the shot‐to‐shot evolution of near‐Bragg coherent scattering from a single crystalline germanium sample. It is shown that X‐ray photon correlation analysis of sequential speckle patterns measurements can be used to monitor the nature and extent of lattice rearrangements. Abrupt, irreversible changes are observed following intermittent high‐fluence monochromatic X‐ray pulses, thus revealing the existence of a threshold response to X‐FEL pulse intensity.