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arXiv · 0812.0977

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

K. A. Yates·K. Morrison·Jennifer A Rodgers·George BS Penny·Jan-Willem G Bos·J. Paul Attfield·L. F. Cohen
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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.

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K. A. Yates, K. Morrison, Jennifer A Rodgers, George BS Penny, Jan-Willem G Bos, J. Paul Attfield, L. F. Cohen. 2009-03-20. Investigation of Superconducting Gap Structure in TbFeAsO$_{0.9}$F$_{0.1}$ using Point Contact Andreev Reflection. https://doi.org/10.1088/1367-2630/11/2/025015

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