Investigation of Superconducting Gap Structure in TbFeAsO${}_{0.9}$F${}_{0.1}$ using Point Contact Andreev Reflection

Abstract

Bulk samples of TbFeAsO${}_{0.9}$F${}_{0.1}$ (T${}_c$(on) = 50K) were measured by point contact Andreev reflection spectroscopy. The spectra show unambiguous evidence for multiple gap-like features plus the presence of high bias shoulders. By measuring the spectra as a function of temperature with both gold and superconducting niobium tips, we establish that the gap-like features are associated with superconducting order parameter in this material. We discuss whether the well defined zero bias conductance peak that we observe infrequently is associated with a nodal superconducting order parameter.

11 pages, 5 figures, published version

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• Surface Bound States in n-band Systems with Quasiclassical Approach
• Minimal model of point contact Andreev reflection spectroscopy of multiband superconductors
• Data analysis of $ab$ $initio$ effective Hamiltonians in iron-based superconductors $\unicode{x2014}$ Construction of predictors for superconducting critical temperature
• Study of the Two-Gap Superconductivity in GdO(F)FeAs by ScS-Andreev Spectroscopy