Transport Properties of Zigzag Ribbons Composed of Two-Dimensional Quantum Spin Hall Insulators with a Single Magnetic Impurity

We investigate the transport properties of a ribbon with zigzag-shaped edges, which is composed of a two-dimensional quantum spin Hall insulator and contains a single magnetic impurity near the edge. A numerical simulation reveals the nontrivial behavior of the conductance as a function of the energy of an incident electron and the strength of the impurity potential for several locations of the magnetic impurity. The results are discussed by using an analytical approach based on a one-dimensional model with an effective potential obtained by the T-matrix approximation.