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Title: Local pairs and small surfaces.

Abstract

More than 20 years after they were first discovered, high-temperature superconductors remain fundamentally baffling. In superconductors, conduction without electrical resistance arises through the pairing of electrons so as to overcome obstacles to current flow.

Authors:
; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
915023
Report Number(s):
ANL/MSD/JA-59636
TRN: US200817%%67
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Nature News & Views; Journal Volume: 447; Journal Issue: May 31, 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; ELECTRIC CONDUCTIVITY; ELECTRON PAIRS; HIGH-TC SUPERCONDUCTORS

Citation Formats

Julian, S. R., Norman, M. R., Materials Science Division, and Univ. Toronto. Local pairs and small surfaces.. United States: N. p., 2007. Web. doi:10.1038/447537a.
Julian, S. R., Norman, M. R., Materials Science Division, & Univ. Toronto. Local pairs and small surfaces.. United States. doi:10.1038/447537a.
Julian, S. R., Norman, M. R., Materials Science Division, and Univ. Toronto. Thu . "Local pairs and small surfaces.". United States. doi:10.1038/447537a.
@article{osti_915023,
title = {Local pairs and small surfaces.},
author = {Julian, S. R. and Norman, M. R. and Materials Science Division and Univ. Toronto},
abstractNote = {More than 20 years after they were first discovered, high-temperature superconductors remain fundamentally baffling. In superconductors, conduction without electrical resistance arises through the pairing of electrons so as to overcome obstacles to current flow.},
doi = {10.1038/447537a},
journal = {Nature News & Views},
number = May 31, 2007,
volume = 447,
place = {United States},
year = {Thu May 31 00:00:00 EDT 2007},
month = {Thu May 31 00:00:00 EDT 2007}
}
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  • A model of the electronic structure of metal-oxide compounds is applied to the calculation of the oxide conductivity above the superconducting transition. The model takes into account both localized pairs of electrons or holes and itinerant (delocalized) electrons or holes. The magnitude of the estimated conductivity is in accord with experimental results and behaves as a function of temperature as {ital T}{sup {minus}2} or {ital T}{sup {minus}1} depending on the assumption of weak or strong correlation between the pair occupation fluctuations at different lattice sites. The cutoff frequency for pair conductivity scales linearly with temperature. This compares favorably with amore » Drude-model analysis of experimental results for the optical conductivity in terms of a scattering rate with linear {ital T} dependence.« less