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arXiv · 2203.01759

Berry-phase switch in electrostatically-confined topological surface states

Jun Zhang·Ye-ping Jiang·Xu-Cun Ma·Qi-Kun Xue
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Abstract

Here we visualize the trapping of topological surface states in the circular n-p junctions on the top surface of the 7-quintuple-layer three dimensional (3D) topological insulator (TI) Sb2Te3 epitaxial films. As shown by spatially- and field-dependent tunneling spectra, these trapped resonances show field-induced splittings between the degenerate time-reversal-symmetric states at zero magnetic field. These behaviors are attributed unambiguously to Berry-phase switch by comparing the experimental data with both numerical and semi-classical simulations. The successful electrostatic trapping of topological surface states in epitaxial films and the observation of Berry-phase switch provide a rich platform of exploiting new ideas for TI-based quantum devices.

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Jun Zhang, Ye-ping Jiang, Xu-Cun Ma, Qi-Kun Xue. 2022-03-03. Berry-phase switch in electrostatically-confined topological surface states. https://doi.org/10.1103/physrevlett.128.126402

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