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Real-space renormalization group study of the Hubbard model on a non-bipartite lattice

J. X. Wang·Sabre Kais·R. D. Levine
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Abstract

We present the real-space block renormalization group equations for fermion systems described by a Hubbard Hamiltonian on a triangular lattice with hexagonal blocks. The conditions that keep the equations from proliferation of the couplings are derived. Computational results are presented including the occurrence of a first-order metal-insulator transition at the critical value of $U/t \approx 12.5$.

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J. X. Wang, Sabre Kais, R. D. Levine. 2002-02-23. Real-space renormalization group study of the Hubbard model on a non-bipartite lattice. https://arxiv.org/abs/cond-mat/0202413

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