Berry-Phase Switch in Electrostatically Confined Topological Surface States

作者：Zhang, Jun; Jiang, Ye-Ping^*; Ma, Xu-Cun; Xue, Qi-Kun

来源：Physical Review Letters, 2022, 128(12): 126402.

DOI：10.1103/PhysRevLett.128.126402

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Here, we visualize the trapping of topological surface states in the circular n-p junctions on the top surface of the seven-quintuple-layer three dimensional (3D) topological insulator (TI) Sb2Te3 epitaxial films. As shown by spatially dependent 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 semiclassical 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.

• 单位
  清华大学