Open AccessFluorescence X‐ray absorption spectroscopy using a Ge pixel array detector: application to high‐temperature superconducting thin‐film single crystals
Author(s) -
Oyanagi H.,
Tsukada A.,
Naito M.,
Saini N. L.,
Lampert M.O.,
Gutknecht D.,
Dressler P.,
Ogawa S.,
Kasai K.,
Mohamed S.,
Fukano A.
Publication year - 2006
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/s0909049506015251
Subject(s) - materials science , thin film , extended x ray absorption fine structure , spectroscopy , optics , absorption (acoustics) , substrate (aquarium) , molecular beam epitaxy , fluorescence spectroscopy , optoelectronics , epitaxy , absorption spectroscopy , analytical chemistry (journal) , fluorescence , chemistry , nanotechnology , physics , oceanography , layer (electronics) , quantum mechanics , chromatography , geology , composite material
A Ge pixel array detector with 100 segments was applied to fluorescence X‐ray absorption spectroscopy, probing the local structure of high‐temperature superconducting thin‐film single crystals (100 nm in thickness). Independent monitoring of pixel signals allows real‐time inspection of artifacts owing to substrate diffractions. By optimizing the grazing‐incidence angle θ and adjusting the azimuthal angle ϕ, smooth extended X‐ray absorption fine structure (EXAFS) oscillations were obtained for strained (La,Sr) 2 CuO 4 thin‐film single crystals grown by molecular beam epitaxy. The results of EXAFS data analysis show that the local structure (CuO 6 octahedron) in (La,Sr) 2 CuO 4 thin films grown on LaSrAlO 4 and SrTiO 3 substrates is uniaxially distorted changing the tetragonality by ∼5 × 10 −3 in accordance with the crystallographic lattice mismatch. It is demonstrated that the local structure of thin‐film single crystals can be probed with high accuracy at low temperature without interference from substrates.