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Localized Bosonic Modes in Superconductors

Dirk K. Morr·Roy H. Nyberg
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Abstract

We show that a localized bosonic mode acts as a new type of "defect" in s- and d_{x^2-y^2}-wave superconductors. The mode induces bound or resonance states, whose spectral signature are peaks in the superconductor's density of states (DOS). We study the peaks' shape and energy as a function of temperature and the mode's frequency and lifetime. We identify several characteristic signatures of the localized mode that qualitatively distinguishes its effects from those of magnetic or non-magnetic impurities.

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Dirk K. Morr, Roy H. Nyberg. 2003-04-07. Localized Bosonic Modes in Superconductors. https://doi.org/10.1103/physrevb.68.060505

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