Ferromagnetism in the Hubbard Model on fcc-type lattices

TL;DR

This paper investigates ferromagnetism in the Hubbard model on fcc lattices using dynamical mean-field theory, revealing a phase transition to a polarized metallic state and identifying conditions for ferromagnetism.

Contribution

It provides the first detailed analysis of ferromagnetism in the Hubbard model on fcc lattices within dynamical mean-field theory, including phase transition characterization and Curie temperature calculations.

Findings

Finite temperature QMC shows a second order phase transition to ferromagnetism.

Curie temperatures depend on electronic density and interaction strength.

A large spectral weight near band edges is necessary for ferromagnetism.

Abstract

The Hubbard model on fcc-type lattices is studied in the dynamical mean-field theory of infinite spatial dimensions. At intermediate interaction strength finite temperature Quantum Monte Carlo calculations yield a second order phase transition to a highly polarized, metallic ferromagnetic state. The Curie temperatures are calculated as a function of electronic density and interaction strength. A necessary condition for ferromagnetism is a density of state with large spectral weight near one of the band edges.