Analytical and numerical study of the out-of-equilibrium current through a helical edge coupled to a magnetic impurity

  title={Analytical and numerical study of the out-of-equilibrium current through a helical edge coupled to a magnetic impurity},
  author={Yuval Vinkler-Aviv and Daniel May and Frithjof B. Anders},
  journal={Physical Review B},
We study the conductance of a time-reversal symmetric helical electronic edge coupled antiferromagnetically to a magnetic impurity, employing analytical and numerical approaches. The impurity can reduce the perfect conductance $G_0$ of a noninteracting helical edge by generating a backscattered current. The backscattered steady-state current tends to vanish below the Kondo temperature $T_K$ for time-reversal symmetric setups. We show that the central role in maintaining the perfect conductance… 

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