Magnetically stable zero-bias anomaly in Andreev contact to the magnetic Weyl semimetal Co₃Sn₂S₂

Institute of Solid State Physics of the Russian Academy of Sciences - 2 Academician Ossipyan str., 142432 Chernogolovka, Moscow District, Russia

Received: 4 August 2020
Accepted: 13 November 2020

Abstract

Being encouraged by the interplay between topology, superconductivity and magnetism, we experimentally investigate charge transport through the interface between the Nb superconductor and the time-reversal symmetry breaking Weyl semimetal Co₃Sn₂S₂. In addition to the proximity-induced superconducting gap, we observe prominent subgap zero-bias anomaly. The anomaly demonstrates an unusual robustness to external magnetic fields: its width is absolutely stable up to the critical field of Nb, while its amplitude exhibits a weak non-monotonous variation. As the promising scenario of emergence of the zero-bias anomaly in transport characteristics, we consider the proximity-induced zero-energy Andreev bound states interfaced with the half-metallic Co₃Sn₂S₂ and influenced by the strong spin-orbit coupling and large Zeeman splitting.