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arXiv · 2410.17786

Anomalous conductance steps in three-dimensional topological insulator HgTe-based quantum point contacts

Elisabeth Richter·Michael Barth·Dmitriy A. Kozlov·Angelika Knothe·Nikolay N. Mikhailov·Juliane Steidl·Cosimo Gorini·Stefan Hartl·Wolfgang Himmler·Klaus Richter·Dieter Weiss
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Abstract

We explore electrical transport through a point contact in strained HgTe, a three-dimensional topological insulator. In the absence of a magnetic field $B$, there is no quantization. However, under higher magnetic fields, we observe distinct non-integer conductance steps. Based on numerical tight-binding calculations and a phenomenological Landauer-B\"uttiker approach, we attribute these atypical, non-integer quantized plateaus to significant scattering effects at the point contact.

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Elisabeth Richter, Michael Barth, Dmitriy A. Kozlov, Angelika Knothe, Nikolay N. Mikhailov, Juliane Steidl, Cosimo Gorini, Stefan Hartl, Wolfgang Himmler, Klaus Richter, Dieter Weiss. 2024-10-23. Anomalous conductance steps in three-dimensional topological insulator HgTe-based quantum point contacts. https://doi.org/10.1103/physrevresearch.7.013260

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