View in EDS

Reversible switching of the environment-protected quantum spin Hall insulator bismuthene at the graphene/SiC interface.

Saved in:
Bibliographic Details
Title: Reversible switching of the environment-protected quantum spin Hall insulator bismuthene at the graphene/SiC interface.
Authors: Tilgner, Niclas, Wolff, Susanne, Soubatch, Serguei, Lee, Tien-Lin, Peña Unigarro, Andres David, Gemming, Sibylle, Tautz, F. Stefan, Seyller, Thomas, Kumpf, Christian, Göhler, Fabian, Schädlich, Philip
Source: Nature Communications; 7/4/2025, Vol. 16 Issue 1, p1-8, 8p
Abstract: Quantum spin Hall insulators have been extensively studied both theoretically and experimentally because they exhibit robust helical edge states driven by spin-orbit coupling and offer the potential for applications in spintronics through dissipationless spin transport. Here we show that a single layer of elemental Bi, formed by intercalation of an epitaxial graphene buffer layer on SiC(0001), is a promising candidate for a quantum spin Hall insulator. This layer can be reversibly switched between an electronically inactive precursor state and a bismuthene state, the latter exhibiting the predicted band structure of a true two-dimensional bismuthene layer. Switching is accomplished by hydrogenation (dehydrogenation) of the sample. A partial passivation (activation) of Si dangling bonds causes a lateral shift of Bi atoms involving a change of the adsorption site. In the bismuthene state, the Bi honeycomb layer is a prospective quantum spin Hall insulator, inherently protected by the graphene sheet above and the H-passivated substrate below.Tilgner et al. demonstrated the formation of the quantum spin Hall insulator bismuthene on SiC, intercalated underneath a protective graphene layer. A hydrogen-induced orbital filtering effect is the driving force behind this reversible phase transition. [ABSTRACT FROM AUTHOR]
Copyright of Nature Communications is the property of Springer Nature and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Complementary Index
Description
Abstract:Quantum spin Hall insulators have been extensively studied both theoretically and experimentally because they exhibit robust helical edge states driven by spin-orbit coupling and offer the potential for applications in spintronics through dissipationless spin transport. Here we show that a single layer of elemental Bi, formed by intercalation of an epitaxial graphene buffer layer on SiC(0001), is a promising candidate for a quantum spin Hall insulator. This layer can be reversibly switched between an electronically inactive precursor state and a bismuthene state, the latter exhibiting the predicted band structure of a true two-dimensional bismuthene layer. Switching is accomplished by hydrogenation (dehydrogenation) of the sample. A partial passivation (activation) of Si dangling bonds causes a lateral shift of Bi atoms involving a change of the adsorption site. In the bismuthene state, the Bi honeycomb layer is a prospective quantum spin Hall insulator, inherently protected by the graphene sheet above and the H-passivated substrate below.Tilgner et al. demonstrated the formation of the quantum spin Hall insulator bismuthene on SiC, intercalated underneath a protective graphene layer. A hydrogen-induced orbital filtering effect is the driving force behind this reversible phase transition. [ABSTRACT FROM AUTHOR]
ISSN:20411723
DOI:10.1038/s41467-025-60440-x