Advanced approach of superconducting gap function extraction from tunneling experiments

Abstract

An advanced theoretical framework is introduced and examined. Its main idea is to extract properties of the superconducting pairing gap function $\mathrm{\ensuremath{\Delta}}(\ensuremath{\omega})$ in conventional, nearly localized superconductors. To test the approach, we present an experimentally relevant benchmark model with defined normal and superconducting sectors. The developed reverse engineering framework consists of two logic steps. First, dismantle the superconducting density of states into the effects coming from the superconducting pairing and effects inherited from the normal state. Second, extract and reconstruct properties of $\mathrm{\ensuremath{\Delta}}(\ensuremath{\omega})$ and compare it to the superconducting sector of the defined benchmark model. Applying this approach, we can (i) simulate extraction from the actual experimental low-temperature tunneling data and comment on their required properties, and (ii) maintain absolute control above the reconstructed Cooper-pair-influencing properties during ameliorating the individual steps of the method.