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Title: Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation

Abstract

High-quality polarized x-ray absorption spectroscopy data for (La,Sr){sub 2}CuO{sub 4} thin-film single crystals reveal strain-dependent local disorder (in the oxygen radial distribution) that correlates with the superconducting critical temperature. The temperature-dependent in-plane oxygen displacement shows that local lattice distortion strongly depends on strain, i.e., the biaxial tensile strain develops domains with the bond-stretching-type local distortion which is weakened by the compressive strain. We suggest that the two-dimensional strain modifies electronic inhomogeneity that influences the superconducting critical temperature through superfluid density, rather than band structure effects.

Authors:
 [1];  [2];  [3];  [4];  [5]
  1. National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)
  2. NTT Basic Research Laboratories, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)
  3. (Japan)
  4. Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588 (Japan)
  5. Universita di Roma 'La Sapienza', Piazza le Aldo Moro 2, 00185 Rome (Italy)
Publication Date:
OSTI Identifier:
20976652
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevB.75.024511; (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; COPPER COMPOUNDS; CRITICAL TEMPERATURE; DENSITY; HIGH-TC SUPERCONDUCTORS; LANTHANUM COMPOUNDS; MONOCRYSTALS; OXYGEN; SPATIAL DISTRIBUTION; STRAINS; STRESSES; STRONTIUM COMPOUNDS; SUPERFLUIDITY; TEMPERATURE DEPENDENCE; THIN FILMS; TWO-DIMENSIONAL CALCULATIONS; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Oyanagi, H., Tsukada, A., Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588, Naito, M., and Saini, N. L. Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.024511.
Oyanagi, H., Tsukada, A., Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588, Naito, M., & Saini, N. L. Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation. United States. doi:10.1103/PHYSREVB.75.024511.
Oyanagi, H., Tsukada, A., Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588, Naito, M., and Saini, N. L. Mon . "Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation". United States. doi:10.1103/PHYSREVB.75.024511.
@article{osti_20976652,
title = {Local structure of superconducting (La,Sr){sub 2}CuO{sub 4} under strain: Microscopic mechanism of strain-induced T{sub c} variation},
author = {Oyanagi, H. and Tsukada, A. and Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588 and Naito, M. and Saini, N. L.},
abstractNote = {High-quality polarized x-ray absorption spectroscopy data for (La,Sr){sub 2}CuO{sub 4} thin-film single crystals reveal strain-dependent local disorder (in the oxygen radial distribution) that correlates with the superconducting critical temperature. The temperature-dependent in-plane oxygen displacement shows that local lattice distortion strongly depends on strain, i.e., the biaxial tensile strain develops domains with the bond-stretching-type local distortion which is weakened by the compressive strain. We suggest that the two-dimensional strain modifies electronic inhomogeneity that influences the superconducting critical temperature through superfluid density, rather than band structure effects.},
doi = {10.1103/PHYSREVB.75.024511},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 2,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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