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arXiv · 1805.12330

Dirac surface states in superconductors: a dual topological proximity effect

Nicholas Sedlmayr·E. W. Goodwin·Michael Gottschalk·Ian M. Dayton·Can Zhang·Erik Huemiller·Reza Loloee·Thomas C. Chasapis·Maryam Salehi·Nikesh Koirala·Mercouri G. Kanatzidis·Seongshik Oh·D. J. Van Harlingen·Alex Levchenko·S. H. Tessmer
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Abstract

In this paper we present scanning tunneling microscopy of Bi$_2$Se$_3$ with superconducting Nb deposited on the surface. We find that the topologically protected surface states of the Bi$_2$Se$_3$ leak into the superconducting over-layer, suggesting a dual topological proximity effect. Coupling between theses states and the Nb states leads to an effective pairing mechanism for the surface states, leading to a modified model for a topological superconductor in these systems. This model is consistent with fits between the experimental data and the theory.

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Nicholas Sedlmayr, E. W. Goodwin, Michael Gottschalk, Ian M. Dayton, Can Zhang, Erik Huemiller, Reza Loloee, Thomas C. Chasapis, Maryam Salehi, Nikesh Koirala, Mercouri G. Kanatzidis, Seongshik Oh, D. J. Van Harlingen, Alex Levchenko, S. H. Tessmer. 2018-05-31. Dirac surface states in superconductors: a dual topological proximity effect. https://arxiv.org/abs/1805.12330

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