Modeling Unconventional Superconductivity at the Crossover between Strong and Weak Electronic Interactions.

Area of Science:

• Condensed Matter Physics
• Quantum Materials Science

Background:

• High-temperature superconductivity often occurs in quantum materials with comparable electronic kinetic energy and electron-electron repulsion.
• Standard perturbative methods fail to describe these intermediate-coupling regimes.

Purpose of the Study:

• To investigate the interplay of magnetic, superconducting, and charge degrees of freedom in intermediate-coupling regimes.
• To utilize a sign-problem-free multiband Hubbard model for accurate simulations.

Main Methods:

• Employed quantum Monte Carlo (QMC) methods.
• Solved a multiband Hubbard model with repulsive interband interactions.
• Treated magnetic, superconducting, and charge degrees of freedom concurrently.

Main Results:

• Identified an antiferromagnetic dome and a metal-to-insulator crossover line in the intermediate-coupling regime.
• Observed a superconducting dome within the metallic region.
• Found that magnetic fluctuations transition from overdamped to propagating across the antiferromagnetic dome.

Conclusions:

• The study provides insights into the complex relationships between superconductivity, magnetism, and charge correlations in quantum materials.
• Findings highlight the importance of considering multiple degrees of freedom simultaneously in these systems.