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arXiv · 2310.06924

In-plane magnetic field driven conductance modulations in topological insulator kinks

Gerrit Behner·Kristof Moors·Yong Zhang·Michael Schleenvoigt·Alina Rupp·Erik Zimmermann·Abdur Rehman Jalil·Peter Schüffelgen·Hans Lüth·Detlev Grützmacher·Thomas Schäpers
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Abstract

We present low-temperature magnetoconductance measurements on Bi$_{1.5}$Sb$_{0.5}$Te$_{1.8}$Se$_{1.2}$ kinks with ribbon-shaped legs. The conductance displays a clear dependence on the in-plane magnetic field orientation. The conductance modulation is consistent with orbital effect-driven trapping of the topological surface states on different side facets of the legs of the kink, which affects their transmission across the kink. This magnetic field-driven trapping and conductance pattern can be explained with a semiclassical picture and is supported by quantum transport simulations. The interpretation is corroborated by varying the angle of the kink and analyzing the temperature dependence of the observed magnetoconductance pattern, indicating the importance of phase coherence along the cross section perimeter of the kink legs.

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Gerrit Behner, Kristof Moors, Yong Zhang, Michael Schleenvoigt, Alina Rupp, Erik Zimmermann, Abdur Rehman Jalil, Peter Schüffelgen, Hans Lüth, Detlev Grützmacher, Thomas Schäpers. 2024-05-01. In-plane magnetic field driven conductance modulations in topological insulator kinks. https://doi.org/10.1103/physrevb.109.155429

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