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arXiv · 2102.06639

Topological surface currents accessed through reversible hydrogenation of the three-dimensional bulk

Haiming Deng·Lukas Zhao·Kyungwha Park·Jiaqiang Yan·Kamil Sobczak·Lia Krusin-Elbaum
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Abstract

Hydrogen, the smallest and most abundant element in nature, can be efficiently incorporated within a solid and drastically modify its electronic state - it has been known to induce novel magnetoelectric effects in complex perovskites and modulate insulator-to-metal transition in a correlated Mott oxide. Here we demonstrate that hydrogenation resolves an outstanding challenge in chalcogenide classes of three-dimensional (3D) topological insulators and magnets - the control of intrinsic bulk conduction that denies access to quantum surface transport. With electrons donated by a reversible binding of H+ ions to Te(Se) chalcogens, carrier densities are easily changed by over 10^20 cm^-3, allowing tuning the Fermi level into the bulk bandgap to enter surface/edge current channels. The hydrogen-tuned topological materials are stable at room temperature and tunable disregarding bulk size, opening a breadth of platforms for harnessing emergent topological states.

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Haiming Deng, Lukas Zhao, Kyungwha Park, Jiaqiang Yan, Kamil Sobczak, Lia Krusin-Elbaum. 2021-02-12. Topological surface currents accessed through reversible hydrogenation of the three-dimensional bulk. https://doi.org/10.1038/s41467-022-29957-3

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