Orbital structure of the effective pairing interaction in the high-temperature superconducting cuprates

The nature of the effective interaction responsible for pairing in the high-temperature superconducting cuprates remains unsettled. This question has been studied extensively using the simplified single-band Hubbard model, which does not explicitly consider the orbital degrees of freedom of the relevant CuO2 planes. Here, we use a dynamical cluster quantum Monte Carlo approximation to study the orbital structure of the pairing interaction in the three-band Hubbard model, which treats the orbital degrees of freedom explicitly. We find that the interaction predominately acts between neighboring copper orbitals, but with significant additional weight appearing on the surrounding bonding molecular oxygen orbitals. By explicitly comparing these results to those from the simpler single-band Hubbard model, our study provides strong support for the single-band framework for describing superconductivity in the cuprates.

Automated summary

By using a dynamical cluster quantum Monte Carlo approximation, this study investigated the orbital structure of the pairing interaction in the three-band Hubbard model. The research found that the interaction mainly occurs between neighboring copper orbitals, with additional weight appearing on the surrounding bonding molecular oxygen orbitals. Comparing these results to the simpler single-band Hubbard model provides strong support for the single-band framework in describing superconductivity in the cuprates.