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arXiv · 1204.0236

Kosterlitz-Thouless transition in disordered two-dimensional topological insulators

Zhong Xu·L. Sheng·R. Shen·Baigeng Wang·D. Y. Xing
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Abstract

The disorder-driven metal-insulator transition in the quantum spin Hall systems is studied by scaling analysis of the Thouless conductance $g$. Below a critical disorder strength, the conductance is independent of the sample size $M$, an indication of critically delocalized electron states. The calculated beta function $β=d\ln g/d\ln M$ indicates that the metal-insulator transition is Kosterlitz-Thouless (KT) type, which is characterized by bounding and unbounding of vortex-antivortex pairs of the local currents. The KT like metal-insulator transition is a basic characteristic of the quantum spin Hall state, being independent of the time-reversal symmetry.

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Zhong Xu, L. Sheng, R. Shen, Baigeng Wang, D. Y. Xing. 2012-04-01. Kosterlitz-Thouless transition in disordered two-dimensional topological insulators. https://doi.org/10.1088/0953-8984%2F25%2F6%2F065501

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