# Model-mapped random phase approximation to evaluate superconductivity in the fluctuation exchange approximation from first principles

## TL;DR

This paper applies a model-mapped RPA approach combined with first-principles calculations to two cuprate superconductors, successfully explaining their differing critical temperatures and providing insights into interaction terms.

## Contribution

It introduces a first-principles based method to evaluate superconductivity using model-mapped RPA and fluctuation exchange calculations for cuprates.

## Key findings

- Successfully explains the relative Tc of La2CuO4 and HgBa2CuO4
- Provides detailed analysis of interaction terms in the models
- Shows consistency with experimental observations

## Abstract

We have applied the model-mapped RPA [H. Sakakibara et al., J. Phys. Soc. Jpn. 86, 044714 (2017)] to the cuprate superconductors La2CuO4 and HgBa2CuO4, resulting two-orbital Hubbard models. All the model parameters are determined based on first-principles calculations. For the model Hamiltonians, we perform fluctuation exchange calculation. Results explain relative height of Tc observed in experiment for La2CuO4 and HgBa2CuO4. In addition, we give some analyses for the interaction terms in the model, especially comparisons with those of the constrained RPA.