Experimental search for the origin of low-energy modes in topological materials

G. P. Mazur; K. Dybko; A. Szczerbakow; J. Z. Domagala; A. Kazakov; M. Zgirski; E. Lusakowska; S. Kret; J. Korczak; T. Story; M. Sawicki; T. Dietl

doi:10.1103/physrevb.100.041408

arXiv · 1709.04000

Experimental search for the origin of low-energy modes in topological materials

G. P. Mazur·K. Dybko·A. Szczerbakow·J. Z. Domagala·A. Kazakov·M. Zgirski·E. Lusakowska·S. Kret·J. Korczak·T. Story·M. Sawicki·T. Dietl

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Abstract

Point-contact spectroscopy of several non-superconducting topological materials reveals a low temperature phase transition that is characterized by a Bardeen-Cooper-Schrieffer-type of criticality. We find such a behavior of differential conductance for topological surfaces of non-magnetic and magnetic Pb$_{1-y-x}$Sn$_y$Mn$_x$Te. We examine a possible contribution from superconducting nanoparticles, and show to what extent our data are consistent with Brzezicki's et al. theory [arXiv:1812.02168], assigning the observations to a collective state adjacent to atomic steps at topological surfaces.

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G. P. Mazur, K. Dybko, A. Szczerbakow, J. Z. Domagala, A. Kazakov, M. Zgirski, E. Lusakowska, S. Kret, J. Korczak, T. Story, M. Sawicki, T. Dietl. 2019-07-27. Experimental search for the origin of low-energy modes in topological materials. https://doi.org/10.1103/physrevb.100.041408

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