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Effective spinless fermions in the strong coupling Kondo model

Winfried Koller·Alexander Pruell·Hans Gerd Evertz·Wolfgang von der Linden
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Abstract

Starting from the two-orbital Kondo-lattice model with classical t_2g spins, an effective spinless fermion model is derived for strong Hund coupling J_H with a projection technique. The model is studied by Monte Carlo simulations and analytically using a uniform hopping approximation. The results for the spinless fermion model are in remarkable agreement with those of the original Kondo-lattice model, independent of the carrier concentration, and even for moderate Hund coupling J_H. Phase separation, the phase diagram in uniform hopping approximation, as well as spectral properties including the formation of a pseudo-gap are discussed for both the Kondo-lattice and the effective spinless fermion model in one and three dimensions.

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Winfried Koller, Alexander Pruell, Hans Gerd Evertz, Wolfgang von der Linden. 2002-11-21. Effective spinless fermions in the strong coupling Kondo model. https://doi.org/10.1103/physrevb.66.144425

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