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Correlation Effects in a One-Dimensional Quarter-Filled Electron System with Repulsive Interactions

Hideo Yoshioka·Masahisa Tsuchiizu·Yoshikazu Suzumura
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Abstract

A one-dimensional electron system at quarter-filling has been examined by applying the renormalization group method to a bosonized model with on-site (U) and nearest-neighbor (V) repulsive interactions. By evaluating both normal scattering and Umklapp scattering perturbatively, we obtain a phase diagram in which a metallic state with a 2k_F spin density wave (k_F is the Fermi wave number) moves into an insulating state with charge disproportionation of a 4k_F charge density wave with an increase in both U and V. The effect of the next-nearest-neighbor repulsion is also discussed.

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Hideo Yoshioka, Masahisa Tsuchiizu, Yoshikazu Suzumura. 2000-01-31. Correlation Effects in a One-Dimensional Quarter-Filled Electron System with Repulsive Interactions. https://doi.org/10.1143/jpsj.69.651

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