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Low density approach to the Kondo-lattice model

W. Nolting·G. G. Reddy·A. Ramakanth·D. Meyer
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Abstract

We propose a new approach to the (ferromagnetic) Kondo-lattice model in the low density region, where the model is thought to give a reasonable frame work for manganites with perovskite structure exhibiting the "colossal magnetoresistance" -effect. Results for the temperature- dependent quasiparticle density of states are presented. Typical features can be interpreted in terms of elementary spin-exchange processes between itinerant conduction electrons and localized moments. The approach is exact in the zero bandwidth limit for all temperatures and at T=0 for arbitrary bandwidths, fulfills exact high-energy expansions and reproduces correctly second order perturbation theory in the exchange coupling.

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W. Nolting, G. G. Reddy, A. Ramakanth, D. Meyer. 2001-07-04. Low density approach to the Kondo-lattice model. https://doi.org/10.1103/physrevb.64.155109

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