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Stripe orders in the extended Hubbard model

Taira Kato·Masaru Kato
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Abstract

We study stripe orders of charge and spin density waves in the extended Hubbard model with the nearest-neighbor Coulomb repulsion V within the mean field approximation. We obtain V vs. T(temperature) phase diagram for the on-site Coulomb interaction U/t=8.0 and the filling n=0.8, here t is a nearest-neighbor transfer energy. Our result shows that the diagonal stripe spin density wave state (SDW) is stable for small V, but for large V the most stable state changes to a charge density wave-antiferromagnetic (CDW-AF) state. Especially we find at low temperature and for a certain range of value of V, a vertical stripe CDW-AF state becomes stable.

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Taira Kato, Masaru Kato. 2000-03-21. Stripe orders in the extended Hubbard model. https://doi.org/10.1143/jpsj.69.3972

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