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Title: Local lattice structure in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} studied by Cu and Mn K-edge XAFS

Abstract

The local lattice structures in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} are investigated by Cu K-edge and Mn K-edge x-ray-absorption near-edge structure and extended x-ray-absorption fine structure from 10 to 300 K. The results confirm that the doped Mn ions are located at the Cu site of La{sub 2-x}Sr{sub x}CuO{sub 4} phase and the impurity phases, such as La{sub 1-x}Sr{sub x}MnO{sub 3}, are not presented in the samples. It is found that the local lattice structures of Cu are not affected by Mn impurities and the local lattice environments of Mn are similar to those of Cu. We consider that the Mn impurities only break the Cu-O p-d hybridization locally, while the local lattice environments and the superconductivity in the regions away from the impurities remain untouched. This result implicates that local lattice inhomogeneity plays an important role in the mechanism of high-temperature superconductivity.

Authors:
;  [1]; ;  [2];  [3]
  1. National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8568 (Japan)
  2. School of Physics and Nano Systems Institute-National Core Research Center, Seoul National University, Seoul 151-747 (Korea, Republic of)
  3. Structure Research Laboratory, University of Science and Technology of China, Hefei 230026 (China)
Publication Date:
OSTI Identifier:
20957838
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 17; Other Information: DOI: 10.1103/PhysRevB.75.174504; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION SPECTROSCOPY; CRYSTAL STRUCTURE; DOPED MATERIALS; FINE STRUCTURE; HIGH-TC SUPERCONDUCTORS; HYBRIDIZATION; IMPURITIES; LANTHANUM COMPOUNDS; MANGANESE; MANGANESE IONS; STRONTIUM COMPOUNDS; SUPERCONDUCTIVITY; TEMPERATURE RANGE 0400-1000 K; X RADIATION; X-RAY SPECTROSCOPY

Citation Formats

Zhang, C. J., Oyanagi, H., Kim, B. H., Park, Y. W., and Zhang, Y. H. Local lattice structure in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} studied by Cu and Mn K-edge XAFS. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.174504.
Zhang, C. J., Oyanagi, H., Kim, B. H., Park, Y. W., & Zhang, Y. H. Local lattice structure in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} studied by Cu and Mn K-edge XAFS. United States. doi:10.1103/PHYSREVB.75.174504.
Zhang, C. J., Oyanagi, H., Kim, B. H., Park, Y. W., and Zhang, Y. H. Tue . "Local lattice structure in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} studied by Cu and Mn K-edge XAFS". United States. doi:10.1103/PHYSREVB.75.174504.
@article{osti_20957838,
title = {Local lattice structure in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} studied by Cu and Mn K-edge XAFS},
author = {Zhang, C. J. and Oyanagi, H. and Kim, B. H. and Park, Y. W. and Zhang, Y. H.},
abstractNote = {The local lattice structures in Mn-doped La{sub 2-x}Sr{sub x}CuO{sub 4} are investigated by Cu K-edge and Mn K-edge x-ray-absorption near-edge structure and extended x-ray-absorption fine structure from 10 to 300 K. The results confirm that the doped Mn ions are located at the Cu site of La{sub 2-x}Sr{sub x}CuO{sub 4} phase and the impurity phases, such as La{sub 1-x}Sr{sub x}MnO{sub 3}, are not presented in the samples. It is found that the local lattice structures of Cu are not affected by Mn impurities and the local lattice environments of Mn are similar to those of Cu. We consider that the Mn impurities only break the Cu-O p-d hybridization locally, while the local lattice environments and the superconductivity in the regions away from the impurities remain untouched. This result implicates that local lattice inhomogeneity plays an important role in the mechanism of high-temperature superconductivity.},
doi = {10.1103/PHYSREVB.75.174504},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 17,
volume = 75,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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