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arXiv · 1402.7361

Molecular Pairing and Fully-Gapped Superconductivity in Yb doped CeCoIn5

Onur Erten·Rebecca Flint·Piers Coleman
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Abstract

The recent observation of fully-gapped superconductivity in Yb doped CeCoIn5 poses a paradox, for the disappearance of nodes suggests that they are accidental, yet d-wave symmetry with protected nodes is we ll established by experiment. Here, we show that composite pairing provides a natural resolution: in this scenario, Yb doping drives a Lifshitz transition of the nodal Fermi surface, forming a fully-gapped d-wave molecular superfluid of composite pairs. The T4 dependence of the penetration depth associated with the sound mode of this condensate is in accord with observation.

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Onur Erten, Rebecca Flint, Piers Coleman. 2015-01-15. Molecular Pairing and Fully-Gapped Superconductivity in Yb doped CeCoIn5. https://doi.org/10.1103/physrevlett.114.027002

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