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Phase Diagram of Spinless Fermions on an Anisotropic Triangular Lattice at Half-filling

Chisa Hotta·Nobuo Furukawa·Akihiko Nakagawa·Kenn Kubo
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Abstract

The strong coupling phase diagram of the spinless fermions on the anisotropic triangular lattice at half-filling is presented. The geometry of inter-site Coulomb interactions rules the phase diagram. Unconventional charge ordered phases are detected which are the recently reported pinball liquid and the striped chains. Both are induced by the quantum dynamics out of classical disordered states and afford extremely correlated metallic states and the particular domain wall-type of excitations, respectively. The disorder once killed by the quantum effect revives at the finite temperature, which is discussed in the terms of the organic $θ$-ET$_2X$.

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Chisa Hotta, Nobuo Furukawa, Akihiko Nakagawa, Kenn Kubo. 2006-07-27. Phase Diagram of Spinless Fermions on an Anisotropic Triangular Lattice at Half-filling. https://doi.org/10.1143/jpsj.75.123704

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