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Journal of the Physical Society of Japan

Metallic Ferromagnetism in a One-Dimensional Hubbard Model; Study Using the Density-Matrix Renormalization-Group Method

Harumi Sakamoto, Kenn Kubo

Published Dec 15, 1996• 28 citations
Publisher

Abstract

We examined a one-dimensional Hubbard model with nearest- and next-nearest-neighbor hopping with up to 32 sites by means of the density-matrix renormalization-group method. The model has two energy bands and includes the flat-band model studied by Tasaki as a special case. The model with finite band dispersion is found to show metallic (saturated) ferromagnetism for a sufficiently strong interaction. No partially polarized ground state is found. The interaction necessary to realize a ferromagnetic ground state becomes weak when the electron density is decreased from the quarter-filling.

DOI
10.1143/jpsj.65.3732

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