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arXiv:cond-mat/9509060

Dirty Hubbard rings: renormalization group and exact diagonalization studies

弘之 森, Minoru HAMADA

Published Sep 12, 1995• 0 citations
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Abstract

We studied mesoscopic Hubbard rings with impurities using the renormalization group (RG) technique and the exact diagonalizations. The exact diagonalization calculations showed that the charge stiffness normalized by the value of clean system has a peak as a function of electron-electron interactions. Previous RG analysis has succeeded to show the enhancement of the stiffness at weak interactions, but does not show the peak behavior. We derived RG equations with $4k_F$ impurity scattering term, which was ignored in the previous studies, and reproduced the overall behavior of the exact diagonalization results.

DOI
10.48550/arxiv.cond-mat/9509060

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We studied mesoscopic Hubbard rings with impurities using the renormalization group (RG) technique and the exact diagonalizations. The exact diagonalization calculations showed that the charge stiffness normalized by the value of clean system has a peak as a function of electron-electron interactions. Previous RG analysis has succeeded to show the enhancement of the stiffness at weak interactions, but does not show the peak behavior. We derived RG equations with 4kF4k_F4kF​ impurity scattering term, which was ignored in the previous studies, and reproduced the overall behavior of the exact diagonalization results.
We studied mesoscopic Hubbard rings with impurities using the renormalization group (RG) technique and the exact diagonalizations. The exact diagonalization calculations showed that the charge stiffness normalized by the value of a clean system has a peak as a function of electron-electron interactions. Previous RG analysis has succeeded in showing the enhancement of the stiffness at weak interactions, but does not reveal the peak behavior. We derived RG equations with a 4kF{\mathit{k}}_{\mathit{F}}kF​ impurity scattering term, which was ignored in the previous studies, and reproduced the overall behavior of the exact diagonalization results. \textcopyright{} 1996 The American Physical Society.
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