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Ferromagnetism in the Hubbard model with long-range and correlated hopping

Pavol Farkasovsky
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Abstract

The extrapolation of small-cluster exact-diagonalization calculations is used to examine ferromagnetism in the one-dimensional Hubbard model with long-range and correlated hopping. It is found that the correlated hopping term stabilizes the ferromagnetic state for a wide range of electron interactions $U$ and electron concentrations $n$. The critical value of the interaction strength $U_c$ above which the ferromagnetic state becomes stable is calculated numerically and the ground-state phase diagram of the model is presented for physically the most interesting cases.

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Pavol Farkasovsky. 2003-12-18. Ferromagnetism in the Hubbard model with long-range and correlated hopping. https://doi.org/10.1007/s10582-004-0110-7

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