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arXiv · 1009.3278

Origin of the T$_c$ enhancement in heterostructure cuprate superconductors

Doron L. Bergman·Tami Pereg-Barnea
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Abstract

Recent experiments on heterostructures composed of two or more films of cuprate superconductors of different oxygen doping levels\cite{Yuli,Gozar} have shown a remarkable T$_c$ enhancement (up to 50%) relative to single compound films. We provide here a simple explanation of the enhancement which arises naturally from a collection of experimental works. We show that the enhancement could be caused by a structural change in the lattice, namely an increase in the distance of the apical oxygen from the copper-oxygen plane. This increase modifies the effective off-site interaction in the plane which in turn enhances the d-wave superconductivity order parameter. To illustrate this point we study the extended Hubbard model using the fluctuation exchange approximation.

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Doron L. Bergman, Tami Pereg-Barnea. 2010-09-16. Origin of the T$_c$ enhancement in heterostructure cuprate superconductors. https://doi.org/10.3390/ma4101835

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