Helical edge transport in the presence of a magnetic impurity

  title={Helical edge transport in the presence of a magnetic impurity},
  author={Pavel D. Kurilovich and Vladislav D. Kurilovich and Igor S. Burmistrov and M. Goldstein},
  journal={JETP Letters},
  pages={593 - 599}
We consider the effects of electron scattering off a quantum magnetic impurity on the current–voltage characteristics of the helical edge of a two-dimensional topological insulator. We compute the backscattering contribution to the current along the edge for a general form of the exchange interaction matrix and arbitrary value of the magnetic impurity spin. We find that the differential conductance may exhibit a nonmonotonic dependence on the voltage with several extrema. 

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