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Updated: May 29, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Simultaneous quantization of bulk conduction and valence states through adsorption of nonmagnetic impurities on
Marco Bianchi1, Richard C Hatch, Jianli Mi
1Department of Physics and Astronomy, Interdisciplinary Nanoscience Center, Aarhus University, 8000 Aarhus C, Denmark.
Abstract:
Exposing the (111) surface of the topological insulator Bi(2)Se(3) to carbon monoxide results in strong shifts of the features observed in angle-resolved photoemission. The behavior is very similar to an often reported "aging" effect of the surface, and it is concluded that this aging is most likely due to the adsorption of rest gas molecules. The spectral changes are also similar to those recently reported in connection with the adsorption of the magnetic adatom Fe. All spectral changes can be explained by a simultaneous confinement of the conduction band and valence band states. This is possible only because of the unusual bulk electronic structure of Bi(2)Se(3). The valence band quantization leads to spectral features which resemble those of a band gap opening at the Dirac point.
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