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Ferromagnetism in Electronic Models for Manganites

Jose Riera·Karen Hallberg·Elbio Dagotto
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Abstract

Ground state properties of the Kondo model for manganese oxides in one dimension are studied using numerical techniques. The large Hund coupling ($J_{H}$) limit is specially analyzed. A robust region of fully saturated ferromagnetism (FM) is identified at all densities. For open boundary conditions it is shown exactly that the ground state is FM at $J_{H} = \infty$. Hole-spin phase separation competing with FM was also observed when a large exchange $J$ between the $Mn^{3+}$ ions is used. As the spin of the transition metal ion grows, the hole mobility decreases providing a tentative explanation for the differences between Cu-oxides and Mn-oxides.

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Jose Riera, Karen Hallberg, Elbio Dagotto. 1996-10-01. Ferromagnetism in Electronic Models for Manganites. https://doi.org/10.1103/physrevlett.79.713

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