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'Pi State' Induced by Impurities with a Repulsive Interaction

Grzegorz Litak·Mariusz Krawiec
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Abstract

We study the properties of a quantum impurity embedded in a superconducting host. The superconductor is described by the negative U Hubbard model while the impurity introduces a repulsive interaction to the system. We discuss the influence of this `on-impurity' Coulomb repulsion on the local properties (density of states, electron pairing) of the superconductor. We show the condition of pi - like behaviour, defined as two subsystems having a phase difference of pi, in the system by using a proper combination of attractive pairing interaction and repulsive one located at impurity site.

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Grzegorz Litak, Mariusz Krawiec. 2004-11-02. 'Pi State' Induced by Impurities with a Repulsive Interaction. https://doi.org/10.1002/pssb.200460057

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