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arXiv · 0709.0263

Violation of the Luttinger sum rule within the Hubbard model on a triangular lattice

J. Kokalj·P. Prelovsek
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Abstract

The frequency-moment expansion method is developed to analyze the validity of the Luttinger sum rule within the Mott-Hubbard insulator, as represented by the generalized Hubbard model at half filling and large $U$. For the particular case of the Hubbard model with nearest-neighbor hopping on a triangular lattice lacking the particle-hole symmetry results reveal substantial violation of the sum rule.

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J. Kokalj, P. Prelovsek. 2007-09-03. Violation of the Luttinger sum rule within the Hubbard model on a triangular lattice. https://doi.org/10.1140/epjb/e2008-00264-0

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