Open AccessComparing the spatial coherence of the natural and focused X-rays from a free electron laser
Author(s) -
Do-Hyung Cho,
Jiseok Yang,
Sang-soo Kim,
Daewoong Nam,
Jaehyun Park,
Sunam Kim,
Kensuke Tono,
Makina Yabashi,
Tetsuya Ishikawa,
Changyong Song
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.019573
Subject(s) - optics , coherence (philosophical gambling strategy) , laser , radiation , physics , free electron laser , ptychography , wavefront , diffraction , coherence length , degree of coherence , spatial coherence , coherence time , coherence theory , beam (structure) , superconductivity , quantum mechanics
The degree of spatial coherence, as basic characteristics of the radiation, becomes an important guide to evaluate the performance of X-rays from newly introduced advanced light sources including the X-ray free electron laser (XFEL). Often the modification of the X-ray wavefronts to fulfill various applications is necessary, but also there is the need to preserve its coherence property. However, experimental investigation directly comparing the coherence property of focused X-ray radiations with the unmodified ones has not been available. We have performed Young's double-slit experiments by recording diffraction patterns both from slit apertures for unfocused XFEL radiation and from pairs of Au nanoparticles for one-micron focused XFEL radiations. The results confirm that the degree of spatial coherence is preserved for well-built K-B focusing mirrors.