Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?

  title={Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?},
  author={Arjun Mani and Colin Benjamin},
  journal={Journal of physics. Condensed matter : an Institute of Physics journal},
  volume={28 14},
  • Arjun Mani, Colin Benjamin
  • Published 1 October 2015
  • Physics
  • Journal of physics. Condensed matter : an Institute of Physics journal
On the surface of 2D topological insulators, 1D quantum spin Hall (QSH) edge modes occur with Dirac-like dispersion. Unlike quantum Hall (QH) edge modes, which occur at high magnetic fields in 2D electron gases, the occurrence of QSH edge modes is due to spin-orbit scattering in the bulk of the material. These QSH edge modes are spin-dependent, and chiral-opposite spins move in opposing directions. Electronic spin has a larger decoherence and relaxation time than charge. In view of this, it is… 

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