SU(4)-symmetric Hubbard model at quarter filling: Insights from the dynamical mean-field approach

TL;DR

This paper uses the dynamical mean-field approach to study the phase transitions and thermodynamic properties of the SU(4)-symmetric Hubbard model at quarter filling, revealing magnetic phases and behaviors relevant for ultracold atom experiments.

Contribution

It provides new insights into magnetic ordering and thermodynamics of the SU(4) Hubbard model at quarter filling using dynamical mean-field theory.

Findings

Identification of two-sublattice and plaquette-ordered antiferromagnetic phases.

Analysis of thermodynamic quantities like double occupancy and entropy.

Hierarchy of critical temperatures driven by entropy.

Abstract

We apply the dynamical mean-field approach to the four-component SU(4)-symmetric Fermi-Hubbard model to study transitions between different magnetically ordered phases as well as the hysteresis behavior in the unordered regime. At quarter filling (one particle per site) on the square lattice we identify both the two-sublattice and plaquette-ordered antiferromagnetic phases with the corresponding entropy-driven hierarchy for critical temperatures. We also analyze the behavior of thermodynamic characteristics: the local double occupancy, compressibility, and entropy per particle, which are relevant for experiments with ultracold alkaline-earth(-like) atoms in optical lattices.