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arXiv · 1803.04455

Probing unconventional superconductivity in proximitized graphene by impurity scattering

Oladunjoye A. Awoga·Annica M. Black-Schaffer
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Abstract

We demonstrate how potential impurities are a very powerful tool for determining the pairing symmetry in graphene proximity-coupled to a spin-singlet superconductor. All d-wave states are characterized by subgap resonances, with spatial patterns clearly distinguishing between nodal and chiral d-wave symmetry, while s-wave states have no subgap resonances. We also find strong supergap impurity resonances associated with the normal state Dirac point. Sub- and supergap resonances only interact at very low doping levels, then causing suppression of the supergap resonances.

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Oladunjoye A. Awoga, Annica M. Black-Schaffer. 2018-06-19. Probing unconventional superconductivity in proximitized graphene by impurity scattering. https://doi.org/10.1103/physrevb.97.214515

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