skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Where do the doped holes go in La{sub 2-x}Sr{sub x}CuO{sub 4}? A close look by XAFS

Abstract

Polarized x-ray absorption fine structure (XAFS) measurements at the La and Sr sites in La{sub 2-x}Sr{sub x}CuO{sub 4} (0.075(less-or-similar sign)x(less-or-similar sign)0.35) indicate that doped holes introduced with Sr are not uniformly distributed in the CuO{sub 2} planes but reside in impurity states with the majority of charge located on CuO{sub 6} octahedra coupled to the Sr dopants by an apical oxygen (denoted as Sr octahedra). A model based on doped hole-induced Jahn Teller (JT) distortions of these Sr octahedra indicates the impurity states are overlapping singlet and triplet ones resulting from pairings of intrinsic and extrinsic holes. The more mobile singlet pairs reside in the CuO{sub 2} planes, are bound by more than 0.1 eV and could Bose-condense into a superconducting state. The predominant appearance of (mostly) out-of plane triplet states at high x intimately related to the 2D-3D crossover in transport properties and could relate to the observed loss of high T{sub c} in the overdoped regime, as confinement of carriers to the CuO{sub 2} planes is reduced. (c) 1999 American Institute of Physics.

Authors:
 [1];  [1];  [1]
  1. Physics Department Box 351560, University of Washington, Seattle, Washington 98195 (United States)
Publication Date:
OSTI Identifier:
20216665
Resource Type:
Journal Article
Journal Name:
AIP Conference Proceedings
Additional Journal Information:
Journal Volume: 483; Journal Issue: 1; Other Information: PBD: 1 Sep 1999; Journal ID: ISSN 0094-243X
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; HIGH-TC SUPERCONDUCTORS; LANTHANUM OXIDES; STRONTIUM OXIDES; COPPER OXIDES; ELECTRONIC STRUCTURE; X-RAY SPECTROSCOPY; PHASE DIAGRAMS; MAGNETIC SUSCEPTIBILITY; EXPERIMENTAL DATA

Citation Formats

Haskel, Daniel, Polinger, Victor, and Stern, Edward A. Where do the doped holes go in La{sub 2-x}Sr{sub x}CuO{sub 4}? A close look by XAFS. United States: N. p., 1999. Web. doi:10.1063/1.59594.
Haskel, Daniel, Polinger, Victor, & Stern, Edward A. Where do the doped holes go in La{sub 2-x}Sr{sub x}CuO{sub 4}? A close look by XAFS. United States. doi:10.1063/1.59594.
Haskel, Daniel, Polinger, Victor, and Stern, Edward A. Wed . "Where do the doped holes go in La{sub 2-x}Sr{sub x}CuO{sub 4}? A close look by XAFS". United States. doi:10.1063/1.59594.
@article{osti_20216665,
title = {Where do the doped holes go in La{sub 2-x}Sr{sub x}CuO{sub 4}? A close look by XAFS},
author = {Haskel, Daniel and Polinger, Victor and Stern, Edward A.},
abstractNote = {Polarized x-ray absorption fine structure (XAFS) measurements at the La and Sr sites in La{sub 2-x}Sr{sub x}CuO{sub 4} (0.075(less-or-similar sign)x(less-or-similar sign)0.35) indicate that doped holes introduced with Sr are not uniformly distributed in the CuO{sub 2} planes but reside in impurity states with the majority of charge located on CuO{sub 6} octahedra coupled to the Sr dopants by an apical oxygen (denoted as Sr octahedra). A model based on doped hole-induced Jahn Teller (JT) distortions of these Sr octahedra indicates the impurity states are overlapping singlet and triplet ones resulting from pairings of intrinsic and extrinsic holes. The more mobile singlet pairs reside in the CuO{sub 2} planes, are bound by more than 0.1 eV and could Bose-condense into a superconducting state. The predominant appearance of (mostly) out-of plane triplet states at high x intimately related to the 2D-3D crossover in transport properties and could relate to the observed loss of high T{sub c} in the overdoped regime, as confinement of carriers to the CuO{sub 2} planes is reduced. (c) 1999 American Institute of Physics.},
doi = {10.1063/1.59594},
journal = {AIP Conference Proceedings},
issn = {0094-243X},
number = 1,
volume = 483,
place = {United States},
year = {1999},
month = {9}
}