Anisotropy of the gap parameter in the hole-doped cuprates

TL;DR

This paper investigates the anisotropic structure of the superconducting gap in hole-doped cuprates, revealing distinct temperature dependencies in different momentum space regions and validating the model with experimental data on YBa2Cu3O7-δ.

Contribution

The study provides a detailed analysis of the gap anisotropy and temperature behavior in hole-doped cuprates, supported by a theoretical model that aligns with experimental observations.

Findings

Antinodal gap is weakly temperature dependent and persists above Tc into the pseudogap phase.

Nodal gap values are strongly temperature dependent.

Theoretical results agree with experimental data for YBa2Cu3O7-δ.

Abstract

The structure of the gap parameter ($\Delta_{k}$) for the hole-doped cuprates has been studied. The obtained results indicate that the antinodal part of $\Delta_{k}$ is very weakly temperature dependent and above the critical temperature ($T_{C}$), it extends into the anomalous normal state to the pseudogap temperature. On the other hand, the values of $\Delta_{k}$, which are close to the nodal part, are strongly temperature dependent. The model has been tested for the ${\rm YBa_{2}Cu_{3}O_{7-\delta}}$ superconductor. It has been shown that the theoretical results agree with the experimental data.