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arXiv · cond-mat/9912195

The local spectrum of a superconductor as a probe of interactions between magnetic impurities

Michael E. Flatte·David E. Reynolds
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Abstract

Qualitative differences in the spectrum of a superconductor near magnetic impurity pairs with moments aligned parallel and antiparallel are derived. A proposal is made for a new, nonmagnetic scanning tunneling spectroscopy of magnetic impurity interactions based on these differences. Near parallel impurity pairs the mid-gap localized spin-polarized states associated with each impurity hybridize and form bonding and anti-bonding molecular states with different energies. For antiparallel impurity moments the states do not hybridize; they are degenerate.

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Michael E. Flatte, David E. Reynolds. 1999-12-10. The local spectrum of a superconductor as a probe of interactions between magnetic impurities. https://doi.org/10.1103/physrevb.61.14810

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