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Strong coupling theory of the spinless charges on the triangular lattices: possibility of a new quantum liquid

Chisa Hotta·Nobuo Furukawa
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Abstract

We propose a new type of charge liquid state in the spinless fermion system on a triangular lattice under strong inter-site Coulomb interactions, $V$. In the strong coupling limit ($t=0$), the ground state is classical and disordered due to geometrical frustration. The introduction of small t will drive the system to a partially ordered phase which we call a "pinball liquid". A possibly long range ordered Wigner crystal solid coexist with a liquid component which are moving around them like a pinball. This liquid is dominant over wide range of filling, even away from the regular triangle, and is also realized in the hard core boson systems. Relevance to the organic theta-ET_2X is discsussed.

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Chisa Hotta, Nobuo Furukawa. 2006-05-02. Strong coupling theory of the spinless charges on the triangular lattices: possibility of a new quantum liquid. https://doi.org/10.1103/physrevb.74.193107

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