Superconducting density of states and bandstructure at the surface of the candidate topological superconductor Au2Pb

Francisco Martín-Vega; Edwin Herrera; Beilun Wu; Víctor Barrena; Federico Mompeán; Mar García-Hernández; Paul C. Canfield; Annica M. Black-Schaffer; José J. Baldoví; Isabel Guillamón; Hermann Suderow

doi:10.1103/physrevresearch.4.023241

arXiv · 2205.07094

Superconducting density of states and bandstructure at the surface of the candidate topological superconductor Au2Pb

Francisco Martín-Vega·Edwin Herrera·Beilun Wu·Víctor Barrena·Federico Mompeán·Mar García-Hernández·Paul C. Canfield·Annica M. Black-Schaffer·José J. Baldoví·Isabel Guillamón·Hermann Suderow

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Abstract

The electronic bandstructure of Au$_2$Pb has a Dirac cone which gaps when undergoing a structural transition into a low temperature superconducting phase. This suggests that the superconducting phase ($T_c=1.1$ K) might hold topological properties at the surface. Here we make Scanning Tunneling Microscopy experiments on the surface of superconducting Au$_2$Pb. We measure the superconducting gap and find a sizeable superconducting density of states at the Fermi level. We discuss possible origins for this finding in terms of superconductivity induced into surface states.

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Francisco Martín-Vega, Edwin Herrera, Beilun Wu, Víctor Barrena, Federico Mompeán, Mar García-Hernández, Paul C. Canfield, Annica M. Black-Schaffer, José J. Baldoví, Isabel Guillamón, Hermann Suderow. 2022-05-14. Superconducting density of states and bandstructure at the surface of the candidate topological superconductor Au2Pb. https://doi.org/10.1103/physrevresearch.4.023241

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