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تسجيل مستخدم جديدThermodynamic studies of the two dimensional Falicov-Kimball model on a triangular lattice
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Thermodynamic properties of the spinless Falicov-Kimball model are studied on a triangular lattice using numerical diagonalization technique with Monte-Carlo simulation algorithm. Discontinuous metal-insulator transition is observed at finite temperature. Unlike the case of square lattice, here we observe that the finite temperature effect is not able to smear out the discontinuous metal-insulator transition seen in the ground state. Calculation of specific heat (C_v) shows single and double peak structures for different values of parameters like on-site correlation strength (U), f-electron energy (E_f) and temperature.
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A numerical diagonalization technique with canonical Monte-Carlo simulation algorithm is used to study the phase transitions from low temperature (ordered) phase to high temperature (disordered) phase of spinless Falicov-Kimball model on a triangular
lattice with correlated hopping ($t^{prime}$). It is observed that the low temperature ordered phases (i.e. regular, bounded and segregated) persist up to a finite critical temperature ($T_{c}$). In addition, we observe that the critical temperature decreases with increasing the correlated hopping in regular and bounded phases whereas it increases in the segregated phase. Single and multi peak patterns seen in the temperature dependence of specific heat ($C_v$) and charge susceptibility ($chi$) for different values of parameters like on-site Coulomb correlation strength ($U$), correlated hopping ($t^{prime}$) and filling of localized electrons ($n_{f}$) are also discussed.
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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 $J_{s
e}$ (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 ($N_d$).
Ground state properties of spinless, extended Falicov-Kimball model (FKM) on a finite size triangular lattice with orbital magnetic field normal to the lattice are studied using numerical diagonalization and Monte-Carlo simulation methods. We show th
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