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arXiv · 0712.0905

Two-band ferromagnetic Kondo-lattice model for local-moment half-metals

Michael Kreissl·Wolfgang Nolting
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Abstract

We introduce a two-band Kondo-lattice model to describe ferromagnetic half-metals with local magnetic moments. In a model study, the electronic and magnetic properties are presented by temperature dependent magnetization curves, band-structures, spin polarizations and plasma frequencies. These are obtained from numerically evaluated equations, based on the single-electron Green functions. We show that the mutual influence between the itinerant electrons and the local magnetic moments is responsible for several phase transitions of the half-metals, namely first and second order magnetic phase transitions, as well as half-metal to semiconductor and half-metal to semimetal transitions.

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Michael Kreissl, Wolfgang Nolting. 2007-12-06. Two-band ferromagnetic Kondo-lattice model for local-moment half-metals. https://doi.org/10.1088/0953-8984%2F20%2F03%2F035222

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