Variationnal study of ferromagnetism in the t1-t2 Hubbard chain

S. Daul; P. Pieri; M. Dzierzawa; D. Baeriswyl; P. Fazakas

doi:10.1016/s0921-4526(96)00794-6

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Variationnal study of ferromagnetism in the t1-t2 Hubbard chain

S. Daul·P. Pieri·M. Dzierzawa·D. Baeriswyl·P. Fazakas

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Abstract

A one-dimensional Hubbard model with nearest and (negative) next-nearest neighbour hopping is studied variationally. This allows to exclude saturated ferromagnetism for $U < U_c$. The variational boundary $U_c (n)$ has a minimum at a ``critical density'' $n_c$ and diverges for $n \rightarrow 1$.

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S. Daul, P. Pieri, M. Dzierzawa, D. Baeriswyl, P. Fazakas. 1996-09-20. Variationnal study of ferromagnetism in the t1-t2 Hubbard chain. https://doi.org/10.1016/s0921-4526(96)00794-6

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