Parameters of the Effective Singlet-Triplet Model for Band Structure of High-$T_c$ Cuprates by Different Approaches

TL;DR

This paper compares various computational approaches to determine parameters for the effective singlet-triplet model in high-temperature cuprate superconductors, achieving consistent results that align well with experimental data.

Contribution

It introduces a comprehensive parameter set for the effective model of high-$T_c$ cuprates derived from multiple computational methods, enhancing quantitative understanding.

Findings

Parameters from different methods agree closely.

The parameters match experimental data well.

The set enables better modeling of hole-doped cuprates.

Abstract

The present paper covers the problem of parameters determination for High-$T_c$ superconductive copper oxides. Different approaches, {\it ab initio} LDA and LDA+U calculations and Generalized Tight-Binding (GTB) method for strongly correlated electron systems, are used to calculate hopping and exchange parameters of the effective singlet-triplet model for $CuO_2$-layer. The resulting parameters are in remarkably good agreement with each other and with parameters extracted from experiment. This set of parameters is proposed for proper quantitative description of physics of hole doped High-$T_c$ cuprates in the framework of effective models.