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arXiv · 0707.2239

Saddle-point van Hove singularity and the phase diagram of high-Tc cuprates

J. G. Storey·J. L. Tallon·G. V. M. Williams
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Abstract

We examine the generic phase behavior of high-Tc cuprate superconductors in terms a universal van Hove singularity in the strongly overdoped region. Using a rigid ARPES-derived dispersion we solve the BCS gap equation and show that the pairing interaction or pairing energy cutoff must be a rapidly declining function of doping. This result is prejudicial to a phonon-based pairing interaction and more consistent with a magnetic or magnetically enhanced interaction.

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J. G. Storey, J. L. Tallon, G. V. M. Williams. 2007-07-15. Saddle-point van Hove singularity and the phase diagram of high-Tc cuprates. https://doi.org/10.1103/physrevb.76.174522

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