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arXiv · 2112.09731

Model-independent determination of the gap function of nearly localized superconductors

Dušan Kavický·František Herman·Richard Hlubina
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Abstract

The gap function $\Delta(\omega)$ carries essential information on both, the pairing glue as well as the pair-breaking processes in a superconductor. Unfortunately, in nearly localized superconductors with a non-constant density of states in the normal state, the standard procedure for extraction of $\Delta(\omega)$ cannot be applied. Here, we introduce a model-independent method that makes it possible to extract $\Delta(\omega)$ also in this case. The feasibility of the procedure is demonstrated on the tunneling data for the disordered thin films of TiN. We find an unconventional feature of $\Delta(\omega)$ which suggests that the electrons in TiN are coupled to a very soft pair-breaking mode.

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Dušan Kavický, František Herman, Richard Hlubina. 2021-12-17. Model-independent determination of the gap function of nearly localized superconductors. https://doi.org/10.1103/physrevb.105.214504

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