Open AccessEnhancement of the Refl‐EXAFS sensitivity using the whispering gallery effect
Author(s) -
Chernov V.,
Mytnichenko S. V.,
Lee J.
Publication year - 1999
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/s090904959801810x
Subject(s) - sensitivity (control systems) , extended x ray absorption fine structure , whispering gallery wave , materials science , optics , physics , laser , absorption spectroscopy , engineering , electronic engineering
A new approach to enhancing the sensitivity for the reflection EXAFS signal is described. A method that uses the whispering gallery effect was realized in principle, implementing the optical guiding effect by a simple curved-mirror geometry. The multiple total reflection (MTR) phenomenon highly increases x-ray interaction with the waveguide surface and hence offers higher sensitivity compared to conventional (single reflection) REFLEXAFS. The Ge K-edge REFL-EXAFS measurements were performed using both the MTR and conventional (single reflection) techniques for a GeO2 3 ,~, thick film grown on a silica mirror. The MTR technique allows one to achieve about 20-fold gain in the signal-to-background ratio compared to the conventional technique.