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arXiv · 1504.03429

Study of ground state phases for spin-1/2 Falicov-Kimball model on a triangular lattice

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

The spin-dependent Falicov-Kimball model (FKM) is studied on a triangular lattice using numerical diagonalization technique and Monte-Carlo simulation algorithm. Magnetic properties have been explored for different values of parameters: on-site Coulomb correlation $U$, exchange interaction $J$ and filling of electrons. We have found that the ground state configurations exhibit long range Neèl order, ferromagnetism or a mixture of both as $J$ is varied. The magnetic moments of itinerant ($d$) and localized ($f$) electrons are also studied. For the one-fourth filling case we found no magnetic moment from $d$- and $f$-electrons for $U$ less than a critical value.

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Sant Kumar, Umesh K. Yadav, T. Maitra, Ishwar Singh. 2015-04-14. Study of ground state phases for spin-1/2 Falicov-Kimball model on a triangular lattice. https://doi.org/10.1016/j.ssc.2014.03.014

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