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Updated: Oct 25, 2026

Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Protected Metallic Edge States in a Graphene-Capped Quantum Spin Hall System
Huu Thoai Ngo1, Zamin Mamiyev1, Niclas Tilgner1,2
1Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, ChemnitzD-09126, Germany.
Abstract:
Epitaxial bismuthene on SiC(0001) hosts symmetry-protected metallic edge states within a large bulk band gap, establishing it as a promising two-dimensional topological insulator for high-temperature quantum spin Hall (QSH) transport. Here we realize bismuthene islands by intercalating Bi beneath zero-layer graphene on SiC(0001) followed by hydrogen treatment, yielding well-defined edge terminations. Spectroscopic measurements demonstrate the metallic edge states originating from the underlying bismuthene layer. The graphene overlayer interacts only weakly with the bismuthene, preserving its topological character while providing environmental protection. Overall, our results establish graphene-capped bismuthene as a robust and tunable platform for studying correlated quantum states, with the one-dimensional edge channels exhibiting signatures of electronic correlation effects.
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