Open AccessX‐ray near‐field speckle: implementation and critical analysis
Author(s) -
Lu Xinhui,
Mochrie S. G. J.,
Narayanan S.,
Sandy A. R.,
Sprung M.
Publication year - 2011
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/s0909049511037149
Subject(s) - speckle pattern , optics , coherence (philosophical gambling strategy) , scattering , advanced photon source , physics , synchrotron radiation , detector , near and far field , aperture (computer memory) , synchrotron , photon , beam (structure) , particle accelerator , quantum mechanics , acoustics
The newly introduced coherence‐based technique of X‐ray near‐field speckle (XNFS) has been implemented at 8‐ID‐I at the Advanced Photon Source. In the near‐field regime of high‐brilliance synchrotron X‐rays scattered from a sample of interest, it turns out that, when the scattered radiation and the main beam both impinge upon an X‐ray area detector, the measured intensity shows low‐contrast speckles, resulting from interference between the incident and scattered beams. A micrometer‐resolution XNFS detector with a high numerical aperture microscope objective has been built and its capability for studying static structures and dynamics at longer length scales than traditional far‐field X‐ray scattering techniques is demonstrated. Specifically, the dynamics of dilute silica and polystyrene colloidal samples are characterized. This study reveals certain limitations of the XNFS technique, especially in the characterization of static structures, which is discussed.