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Localized spin ordering in Kondo lattice models

I. P. McCulloch·A. Juozapavicius·A. Rosengren·M. Gulacsi
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Abstract

Using a non-Abelian density matrix renormalization group method we determine the phase diagram of the Kondo lattice model in one dimension, by directly measuring the magnetization of the ground-state. This allowed us to discover a second ferromagnetic phase missed in previous approaches. The phase transitions are found to be continuous. The spin-spin correlation function is studied in detail, and we determine in which regions the large and small Fermi surfaces dominate. The importance of double-exchange ordering and its competition with Kondo singlet formation is emphasized in understanding the complexity of the model.

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I. P. McCulloch, A. Juozapavicius, A. Rosengren, M. Gulacsi. 2001-11-20. Localized spin ordering in Kondo lattice models. https://doi.org/10.1103/physrevb.65.052410

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