Conductance distributions in disordered quantum spin-Hall systems

Abstract

We study numerically the charge conductance distributions of disordered quantum spin-Hall (QSH) systems using a quantum network model. We have found that the conductance distribution at the metal-QSH insulator transition is clearly different from that at the metal-ordinary insulator transition. Thus the critical conductance distribution is sensitive not only to the boundary condition but also to the presence of edge states in the adjacent insulating phase. We have also calculated the point-contact conductance. Even when the two-terminal conductance is approximately quantized, we find large fluctuations in the point-contact conductance. Furthermore, we have found a semi-circular relation between the average of the point-contact conductance and its fluctuation.

9 pages, 17 figures, published version

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Cited by in corpus (8)

• Disordered weak and strong topological insulators
• Phase Structure of the Topological Anderson Insulator
• Multicriticality of Two-dimensional Class D Disordered Topological Superconductors
• Conductance fluctuations in disordered 2D topological insulator wires: From quantum spin-Hall to ordinary quantum phases
• Unconventional scaling theory in disorder-driven quantum phase transition
• Anomalous Hall conductivity and quantum friction
• Critical exponent for the quantum spin Hall transition in Z_2 network model
• Spin-mixing-tunneling network model for Anderson transitions in two-dimensional disordered spinful electrons