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arXiv · cond-mat/0603423

Low energy physical properties of high-Tc superconducting Cu oxides: A comparison between the resonating valence bond and experiments

Abstract

In a recent review by Anderson and coworkers\cite{Vanilla}, it was pointed out that an early resonating valence bond (RVB) theory is able to explain a number of unusual properties of high temperature superconducting (SC) Cu-oxides. Here we extend previous calculations \cite{anderson87,FC Zhang,Randeria} to study more systematically low energy physical properties of the plain vanilla d-wave RVB state, and to compare results with the available experiments. We use a renormalized mean field theory combined with variational Monte Carlo and power Lanczos methods to study the RVB state of an extended $t-J$ model in a square lattice with parameters suitable for the hole doped Cu-oxides. The physical observable quantities we study include the specific heat, the linear residual thermal conductivity, the in-plane magnetic penetration depth, the quasiparticle energy at the antinode $(π, 0)$, the superconducting energy gap, the quasiparticle spectra and the Drude weight. The traits of nodes (including $k_{F}$, the Fermi velocity $v_{F}$ and the velocity along Fermi surface $v_{2}$), as well as the SC order parameter are also studied. Comparisons of the theory and the experiments in cuprates show an overall qualitative agreement, especially on their doping dependences.

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BibTeXRIS

Kai-Yu Yang, C. T. Shih, C. P. Chou, S. M. Huang, T. K. Lee, T. Xiang, F. C. Zhang. 2006-09-30. Low energy physical properties of high-Tc superconducting Cu oxides: A comparison between the resonating valence bond and experiments. https://doi.org/10.1103/physrevb.73.224513

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