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

TL;DR

This paper systematically studies low energy properties of high-Tc cuprate superconductors using a resonating valence bond model, comparing theoretical results with experimental data to assess the model's validity.

Contribution

It extends previous RVB calculations with advanced methods to comprehensively compare theoretical predictions with experimental observations in cuprates.

Findings

Qualitative agreement between theory and experiment on doping dependence

Consistent results for quasiparticle spectra and superconducting gap

Insights into the nodal properties and SC order parameter

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 $(\pi, 0)$, 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.