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

TL;DR

This study investigates the magnetic ground states of the spin-1/2 Falicov-Kimball model on a triangular lattice, revealing various magnetic orders depending on interaction parameters through numerical methods.

Contribution

It provides a detailed numerical analysis of magnetic phases in the spin-dependent Falicov-Kimball model on a triangular lattice, highlighting the effects of Coulomb and exchange interactions.

Findings

Ground states show long-range Neel order, ferromagnetism, or mixed phases as J varies.

No magnetic moments for d- and f-electrons at low U in quarter filling.

Magnetic properties depend critically on interaction parameters.

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 Ne\`el 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.