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One-particle spectral properties of the t-J-$V$ model on the triangular lattice near charge order

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 نشر من قبل Andres Greco
 تاريخ النشر 2008
  مجال البحث فيزياء
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We study the t-J-$V$ model beyond mean field level at finite doping on the triangular lattice. The Coulomb repulsion $V$ between nearest neighbors brings the system to a charge ordered state for $V$ larger than a critical value $V_c$. One-particle spectral properties as self-energy, spectral functions and the quasiparticle weight are studied near and far from the charge ordered phase. When the system approaches the charge ordered state, charge fluctuations become soft and they strongly influence the system leading to incoherent one-particle excitations. Possible implications for cobaltates are given.



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