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

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.

12 pages, 12 figures

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Cited by in corpus (1)

• Advanced approach of superconducting gap function extraction from tunneling experiments