Photoemission-induced gating of topological insulators

  title={Photoemission-induced gating of topological insulators},
  author={Alexander A. Kordyuk and Timur K. Kim and Volodymyr B. Zabolotnyy and D. V. Evtushinsky and Martin Bauch and Christian Hess and Bernd B{\"u}chner and Helmuth Berger and Sergey V. Borisenko},
  journal={Physical Review B},
The recently discovered topological insulators exhibit topologically protected metallic surface states which are interesting from the fundamental point of view and could be useful for various applications if an appropriate electronic gating can be realized. Our photoemission study of Cu-intercalated Bi2Se3 shows that the surface-state occupancy in this material can be tuned by changing the photon energy and understood as a photoemission-induced gating effect. Our finding provides an effective… 

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