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arXiv · 1403.4611

Phase diagram and excitations of a Shiba molecule

N. Y. Yao·C. P. Moca·I. Weymann·J. D. Sau·M. D. Lukin·E. A. Demler·G. Zaránd
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Abstract

We analyze the phase diagram associated with a pair of magnetic impurities trapped in a superconducting host. The natural interplay between Kondo screening, superconductivity and exchange interactions leads to a rich array of competing phases, whose transitions are characterized by discontinuous changes of the total spin. Our analysis is based on a combination of numerical renormalization group techniques as well as semi-classical analytics. In addition to the expected screened and unscreened phases, we observe a new molecular doublet phase where the impurity spins are only partially screened by a single extended quasiparticle. Direct signatures of the various Shiba molecule states can be observed via RF spectroscopy.

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N. Y. Yao, C. P. Moca, I. Weymann, J. D. Sau, M. D. Lukin, E. A. Demler, G. Zaránd. 2014-03-18. Phase diagram and excitations of a Shiba molecule. https://doi.org/10.1103/physrevb.90.241108

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