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Exact solutions of domain wall and spiral ground states in Hubbard models

Makoto Homma·Chigak Itoi
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Abstract

We construct a set of exact ground states with a localized ferromagnetic domain wall and an extended spiral structure in a deformed flat-band Hubbard model. In the case of quarter filling, we show the uniqueness of the ground state with a fixed magnetization. We discuss more realistic situation given by a band-bending perturbation, which can stabilize these curious structures. We study the scattering of a conduction electron by the domain wall and the spiral spins.

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Makoto Homma, Chigak Itoi. 2004-01-23. Exact solutions of domain wall and spiral ground states in Hubbard models. https://doi.org/10.1143/jpsj.73.499

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