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Exact many-electron ground states on the diamond Hubbard chain

Zsolt Gulacsi·Arno Kampf·Dieter Vollhardt
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Abstract

Exact ground states of interacting electrons on the diamond Hubbard chain in a magnetic field are constructed which exhibit a wide range of properties such as flat-band ferromagnetism and correlation induced metallic, half-metallic or insulating behavior. The properties of these ground states can be tuned by changing the magnetic flux, local potentials, or electron density.

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Zsolt Gulacsi, Arno Kampf, Dieter Vollhardt. 2007-03-30. Exact many-electron ground states on the diamond Hubbard chain. https://doi.org/10.1103/physrevlett.99.026404

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