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arXiv · 1201.2881

Observation of multiple superconducting gaps in Fe1+yTe1-xSex via a nano-scale approach to point-contact spectroscopy

Haibing Peng·Debtanu De·Zheng Wu·Carlos Diaz-Pinto
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Abstract

We report a distinct experimental approach to point-contact Andreev reflection spectroscopy with diagnostic capability via a unique design of nano-scale normal metal/superconductor devices with excellent thermo-mechanical stability, and have employed this method to unveil the existence of two superconducting energy gaps in iron chalcogenide Fe1+yTe1-xSex which is crucial for understanding its pairing mechanism. This work opens up new opportunities to study gap structures in superconductors and elemental excitations in solids.

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Haibing Peng, Debtanu De, Zheng Wu, Carlos Diaz-Pinto. 2012-10-16. Observation of multiple superconducting gaps in Fe1+yTe1-xSex via a nano-scale approach to point-contact spectroscopy. https://doi.org/10.1088/0953-8984%2F24%2F45%2F455703

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