From microscopic description to statistical mechanics of Cu-O chain fragments in the high-Tc superconductors REBa_2Cu_3O_{6+x}

H. Haugerud; G. Uimin; W. Selke

doi:10.1016/s0921-4534(97)00002-6

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From microscopic description to statistical mechanics of Cu-O chain fragments in the high-Tc superconductors REBa_2Cu_3O_{6+x}

H. Haugerud·G. Uimin·W. Selke

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Abstract

The oxygen deficient CuO_x planes of the high-Tc superconductors REBa_2Cu_3O_{6+x} (RE denotes a rare-earth atom or yttrium) are studied. Starting from the Emery model for the Cu-O chain fragments, an extended ASYNNNI model is proposed to describe the statistical mechanics of the CuO_x planes. The model is analysed by using Monte Carlo techniques, computing especially the charge transfer to the CuO$_2$ planes regulating the high-Tc superconductivity, and the concentration of differently coordinated Cu ions.Results are compared to experimental data for various RE cases.

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H. Haugerud, G. Uimin, W. Selke. 1996-12-09. From microscopic description to statistical mechanics of Cu-O chain fragments in the high-Tc superconductors REBa_2Cu_3O_{6+x}. https://doi.org/10.1016/s0921-4534(97)00002-6

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