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arXiv · 1511.00606

Probing quantum capacitance in a 3D topological insulator

D. A. Kozlov·D. Bauer·J. Ziegler·R. Fischer·M. L. Savchenko·Z. D. Kvon·N. N. Mikhailov·S. A. Dvoretsky·D. Weiss
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Abstract

We measure the quantum capacitance and probe thus directly the electronic density of states of the high mobility, Dirac type of two-dimensional electron system, which forms on the surface of strained HgTe. Here we show that observed magneto-capacitance oscillations probe, in contrast to magnetotransport, primarily the top surface. Capacitance measurements constitute thus a powerful tool to probe only one topological surface and to reconstruct its Landau level spectrum for different positions of the Fermi energy.

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D. A. Kozlov, D. Bauer, J. Ziegler, R. Fischer, M. L. Savchenko, Z. D. Kvon, N. N. Mikhailov, S. A. Dvoretsky, D. Weiss. 2015-11-02. Probing quantum capacitance in a 3D topological insulator. https://doi.org/10.1103/physrevlett.116.166802

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