Beyond the conventional Emery model: crucial role of long-range hopping for cuprate superconductivity

TL;DR

This paper extends the Emery model for cuprate superconductors by emphasizing the importance of long-range hopping terms, which are crucial for accurately modeling the phase diagram and d-wave superconductivity.

Contribution

It demonstrates that including long-range hopping beyond traditional parameters is essential for realistic modeling of cuprate superconductors.

Findings

Superconducting dome consistent with cuprates using dynamical vertex approximation

Long-range hoppings are necessary for correct phase diagram and d-wave order

Traditional Emery model parameters are insufficient for quantitative accuracy

Abstract

The Emery model is the quintessential model for cuprate superconductors. In his eponymous paper, Emery only considered the next-nearest-neighbor oxygen-copper hopping. Later, also the relevance of nearest- and next-nearest oxygen-oxygen hoppings has been pointed out. Using dynamical vertex approximation, we find a superconducting dome consistent with cuprates. However, long-range hoppings beyond the three conventional hopping parameters are necessary for the quantitatively correct phase diagram and for a proper d-wave order parameter.