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arXiv · 1604.07430

Scanning tunneling microscopy of superconducting topological surface states in Bi$_2$Se$_3$

Ian M. Dayton·Nicholas Sedlmayr·Victor Ramirez·Thomas Chasapis·Reza Loloee·Mercouri Kanatzidis·Alex Levchenko·Stuart Tessmer
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Abstract

In this paper we present scanning tunneling microscopy of a large $\textrm{Bi}_2\textrm{Se}_3$ crystal with superconducting PbBi islands deposited on the surface. Local density of states measurements are consistent with induced superconductivity in the topological surface state with a coherence length of order 540 nm. At energies above the gap the density of states exhibits oscillations due to scattering caused by a nonuniform order parameter. Strikingly, the spectra taken on islands also display similar oscillations along with traces of the Dirac cone, suggesting an inverse topological proximity effect.

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Ian M. Dayton, Nicholas Sedlmayr, Victor Ramirez, Thomas Chasapis, Reza Loloee, Mercouri Kanatzidis, Alex Levchenko, Stuart Tessmer. 2016-06-07. Scanning tunneling microscopy of superconducting topological surface states in Bi$_2$Se$_3$. https://doi.org/10.1103/physrevb.93.220506

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