2016/08/25 by Yan-Feng Zhou, Aimin Guo, Ai-Min Guo +2
Materials Science · Mathematics · Physics and Astronomy · #Condensed matter physics #Electron #Geometry #Graphene research and applications #Landau quantization #Mathematics #Physics #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #Quantum spin Hall effect #Spin (aerodynamics) #Spin Hall effect #Spin engineering #Spin polarization #Surface (topology) #Surface states #Topological Materials and Phenomena #Topological insulator #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.94.085307
published as Phys. Rev. B 94, 085307 (2016) · 6 pages, 5 figures
openalex publication_date 2016/08/25 · openalex created_date 2016/09/16 · arxiv created 2018/04/05 · arxiv updated 2018/04/06 · openalex updated_date 2026/08/05
We study the influence of a step defect on surface states in three-dimensional topological insulators subject to a perpendicular magnetic field. By calculating the energy spectrum of the surface states, we find that Landau levels (LLs) can form on flat regions of the surface and are distant from the step defect, and several subbands emerge at the side surface of the step defect. The subband which connects to the two zeroth LLs is spin polarized and chiral. In particular, when the electron transports along the side surface, the electron spin direction can be manipulated arbitrarily by gate voltage. Also, no reflection occurs even if the electron spin direction is changed. This provides a fascinating avenue to control the electron spin easily and coherently. In addition, regarding the subbands with a high LL index, there exist spin-momentum locking helical states and the quantum spin Hall effect can appear.