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

K. Held·D. Vollhardt
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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.

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K. Held, D. Vollhardt. 1998-04-23. Microscopic conditions favoring itinerant ferromagnetism: Hund's rule coupling and orbital degeneracy. https://doi.org/10.1007/s100510050468

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