Eur. Phys. J. B 5, 473-478 (1998)
https://doi.org/10.1007/s100510050468

Microscopic conditions favoring itinerant ferromagnetism: Hund's rule coupling and orbital degeneracy^*

Theoretische Physik III, Elektronische Korrelationen und Magnetismus, Universität Augsburg, 86135 Augsburg, Germany

Corresponding author: ^a held@physik.uni-augsburg.de

Received: 26 February 1998
Accepted: 17 April 1998
Published online: 15 October 1998

Abstract

The importance of Hund's rule coupling for the stabilization of itinerant ferromagnetism is investigated within a two-band Hubbard model. The magnetic phase diagram is calculated by finite-temperature quantum Monte-Carlo simulations within the dynamical mean-field theory. Ferromagnetism is found in a broad range of electron fillings whereas antiferromagnetism exists only near half filling. The possibility of orbital ordering at quarter filling is also analyzed.