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arXiv · 1006.2105

Tunneling spectra of strongly coupled superconductors: Role of dimensionality

C. Berthod
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Abstract

We investigate numerically the signatures of collective modes in the tunneling spectra of superconductors. The larger strength of the signatures observed in the high-Tc superconductors, as compared to classical low-Tc materials, is explained by the low dimensionality of these layered compounds. We also show that the strong-coupling structures are dips (zeros in the d2I/dV2 spectrum) in d-wave superconductors, rather than the steps (peaks in d2I/dV2) observed in classical s-wave superconductors. Finally we question the usefulness of effective density of states models for the analysis of tunneling data in d-wave superconductors.

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C. Berthod. 2010-06-10. Tunneling spectra of strongly coupled superconductors: Role of dimensionality. https://doi.org/10.1103/physrevb.82.024504

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