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arXiv · 0903.2107

DMPK Equation for the Edge Transport of Quantum Spin Hall Insulator

Dafang Li·Junren Shi
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Abstract

Using the random matrix theory, we investigate the ensemble statistics of edge transport of a quantum spin Hall insulator with multiple edge states in the presence of quenched disorder. Dorokhov-Mello-Pereyra-Kumar equation applicable for such a system is established. It is found that a two-dimensional quantum spin Hall insulator is effectively a new type of one-dimensional (1D) quantum conductor with the different ensemble statistics from that of the ordinary 1D quantum conductor or the insulator with an even number of Kramers edge pairs. The ensemble statistics provides a physical manifestation of the Z2-classification for the time-reversal invariant insulators.

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Dafang Li, Junren Shi. 2009-05-28. DMPK Equation for the Edge Transport of Quantum Spin Hall Insulator. https://doi.org/10.1103/physrevb.79.241303

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