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arXiv · 1310.3022

Impurity bound states and disorder-induced orbital and magnetic order in the s+- state of Fe-based superconductors

Maria N. Gastiasoro·Brian M. Andersen
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Abstract

We study the presence of impurity bound states within a five-band Hubbard model relevant to iron-based superconductors. In agreement with earlier studies, we find that in the absence of Coulomb correlations there exists a range of repulsive impurity potentials where in-gap states are generated. In the presence of weak correlations, these states are generally pushed to the edges of the gap, whereas for larger correlations the onsite impurity potential induces a local magnetic region which reintroduces the low-energy bound states into the gap.

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Maria N. Gastiasoro, Brian M. Andersen. 2013-10-11. Impurity bound states and disorder-induced orbital and magnetic order in the s+- state of Fe-based superconductors. https://doi.org/10.1007/s10948-013-2153-0

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