Itinerant ferromagnetism in an SU(3) Fermi-Hubbard model at finite temperatures: A dynamical mean-field theory study

TL;DR

This study uses dynamical mean-field theory and quantum Monte Carlo simulations to explore finite-temperature itinerant ferromagnetism in an SU(3) Fermi-Hubbard model, revealing a doping-induced ferromagnetic phase and its transition to paramagnetism.

Contribution

It introduces a comprehensive analysis of SU(3) Fermi-Hubbard model ferromagnetism at finite temperatures, highlighting the phase transition and stability conditions, which were not previously detailed.

Findings

Doped holes induce ferromagnetic order with one component dominating.

The ferromagnetic phase undergoes a first-order transition to a paramagnetic phase.

The stability of ferromagnetism depends on interaction strength, doping, and temperature.

Abstract

We investigate an SU(3) Fermi-Hubbard model on a hypercubic lattice at finite temperatures, combining dynamical mean-field theory with continuous-time quantum Monte Carlo simulations. Taking strong correlations into account carefully, we find a ferromagnetically ordered state, in which one of the three components becomes dominant, when holes are doped away from one-third filling. Furthermore, we demonstrate that this ferromagnetically ordered phase undergoes a first-order transition to a paramagnetic state. We clarify the stability of the ferromagnetically ordered state against interaction strength, hole doping, and temperatures. The relevance of generalized Nagaoka ferromagnetism is also addressed, by comparing the results on the Bethe lattice.