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arXiv · 1402.3160

Phase diagram of the triangular extended Hubbard model

Luca F. Tocchio·Claudius Gros·Xue-Feng Zhang·Sebastian Eggert
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Abstract

We study the extended Hubbard model on the triangular lattice as a function of filling and interaction strength. The complex interplay of kinetic frustration and strong interactions on the triangular lattice leads to exotic phases where long-range charge order, antiferromagnetic order, and metallic conductivity can coexist. Variational Monte Carlo simulations show that three kinds of ordered metallic states are stable as a function of nearest neighbor interaction and filling. The coexistence of conductivity and order is explained by a separation into two functional classes of particles: part of them contributes to the stable order, while the other part forms a partially filled band on the remaining substructure. The relation to charge ordering in charge transfer salts is discussed.

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Luca F. Tocchio, Claudius Gros, Xue-Feng Zhang, Sebastian Eggert. 2014-02-13. Phase diagram of the triangular extended Hubbard model. https://doi.org/10.1103/physrevlett.113.246405

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