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Friedel oscillations induced by non-magnetic impurities in the two-dimensional Hubbard model

W. Ziegler·H. Endres·W. Hanke
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Abstract

We study the interplay of correlations and disorder using an unrestricted Slave-Boson technique in real space. Within the saddle-point approximation, we find Friedel oscillations of the charge density in the vicinity of a nonmagnetic impurity, in agreement with numerical simulations. The corresponding amplitudes are suppressed by repulsive interactions, while attractive correlations lead to a charge-density-wave enhancement. In addition, we investigate the spatial dependence of the local magnetic moment and the formation of a magnetic state at the impurity site.

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W. Ziegler, H. Endres, W. Hanke. 1997-04-23. Friedel oscillations induced by non-magnetic impurities in the two-dimensional Hubbard model. https://doi.org/10.1103/physrevb.58.4362

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