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Flat-band ferromagnetism induced by off-site repulsions

Ryotaro Arita·Yukihiro Shimoi·Kazuhiko Kuroki·Hideo Aoki
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Abstract

Density matrix renormalization group method is used to analyze how the nearest-neighbor repulsion V added to the Hubbard model on 1D triangular lattice and a railway trestle (t-t') model will affect the electron-correlation dominated ferromagnetism arising from the interference (frustration). Obtained phase diagram shows that there is a region in smaller-t' side where the critical on-site repulsion above which the system becomes ferromagnetic is reduced when the off-site repulsion is introduced.

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Ryotaro Arita, Yukihiro Shimoi, Kazuhiko Kuroki, Hideo Aoki. 1998-01-23. Flat-band ferromagnetism induced by off-site repulsions. https://doi.org/10.1103/physrevb.57.10609

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