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Phase transitions in a spinless, extended Falicov-Kimball model on the triangular lattice

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 نشر من قبل Umesh Kumar Yadav Dr.
 تاريخ النشر 2012
  مجال البحث فيزياء
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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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