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Strange behavior of persistent currents in small Hubbard rings

Santanu K. Maiti·J. Chowdhury·S. N. Karmakar
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Abstract

We show exactly that small Hubbard rings exhibit unusual kink-like structures giving anomalous oscillations in persistent current. Singular behavior of persistent current disappears in some cases. In half-filled systems mobility gradually drops to zero with interaction, while it converges to some finite value in non-half-filled cases.

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Santanu K. Maiti, J. Chowdhury, S. N. Karmakar. 2004-11-09. Strange behavior of persistent currents in small Hubbard rings. https://doi.org/10.1016/j.physleta.2004.10.015

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