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arXiv · 2007.11395

The Role of Intra- and Inter-site exchange correlations in the Extended Falicov-Kimball Model on a Triangular Lattice

Sant Kumar·Umesh K. Yadav·T. Maitra·Ishwar Singh
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Abstract

Ground state magnetic properties of the spin-dependent Falicov-Kimball model (FKM) are studied by incorporating the intrasite exchange correlation J (between itinerant $d$- and localized $f$- electrons) and intersite (superexchange) correlation $J_{se}$ (between localized $f$- electrons) on a triangular lattice for two different fillings. Numerical diagonalization and Monte-Carlo techniques are used to determine the ground state magnetic properties. Transitions from antiferromagnetic to ferromagnetic and again to re-entrant antiferromagnetic phase is observed in a wide range of parameter space. The magnetic moments of $d$- and $f$- electrons are observed to depend strongly on the value of $J$, $J_{se}$ and also on the total number of $d$- electrons ($N_d$).

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Sant Kumar, Umesh K. Yadav, T. Maitra, Ishwar Singh. 2020-07-21. The Role of Intra- and Inter-site exchange correlations in the Extended Falicov-Kimball Model on a Triangular Lattice. https://doi.org/10.1016/j.ssc.2015.11.018

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