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arXiv · cond-mat/0310055

Persistent Currents in Small, Imperfect Hubbard Rings

P. Koskinen·M. Manninen
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Abstract

We have done a study with small, imperfect Hubbard rings with exact diagonalization. The results for few-electron rings show, that the imperfection, whether localized or not, nearly always decrease, but can also \emph{increase} the persistent current, depending on the character of the imperfection and the on-site interaction. The calculations are generally in agreement with more specialized studies. In most cases the electron spin plays an important role.

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P. Koskinen, M. Manninen. 2003-10-03. Persistent Currents in Small, Imperfect Hubbard Rings. https://doi.org/10.1103/physrevb.68.195304

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