Itinerant Ferromagnetism in the Periodic Anderson Model

TL;DR

This paper introduces a new mechanism for itinerant ferromagnetism in the Periodic Anderson Model, demonstrating through quantum Monte Carlo and analytical methods that it can produce non-saturated ferromagnetic ground states in certain regimes, relevant to various materials.

Contribution

The paper presents a novel ferromagnetism mechanism within the PAM that does not rely on intra atomic Hund's coupling, expanding understanding of magnetic behavior in correlated electron systems.

Findings

PAM exhibits a non-saturated ferromagnetic ground state in the intermediate valence regime.

The mechanism applies to materials like Ce-based compounds and uranium monochalcogenides.

The new mechanism does not require intra atomic Hund's coupling.

Abstract

We introduce a novel mechanism for itinerant ferromagnetism, based on a simple two-band model. The model includes an uncorrelated and dispersive band hybridized with a second band which is narrow and correlated. The simplest Hamiltonian containing these ingredients is the Periodic Anderson Model (PAM). Using quantum Monte Carlo and analytical methods, we show that the PAM and an extension of it contain the new mechanism and exhibit a non-saturated ferromagnetic ground state in the intermediate valence regime. We propose that the mechanism, which does not assume an intra atomic Hund's coupling, is present in both the iron group and in some f electron compounds like Ce(Rh_{1-x} Ru_x)_3 B_2, La_x Ce_{1-x} Rh_3 B_2 and the uranium monochalcogenides US, USe, and UTe.