A topological characterization of delocalization in a spin-orbit coupling system

D. N. Sheng; Z. Y. Weng

doi:10.1103/physrevb.54.r11070

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A topological characterization of delocalization in a spin-orbit coupling system

D. N. Sheng·Z. Y. Weng

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Abstract

We show that wavefunctions in a two-dimensional (2D) electron system with spin-orbit coupling can be characterized by a topological quantity--the Chern integer due to the existence of the intrinsic Kramers degeneracy. The localization-delocalization transition in such a system is studied in terms of such a Chern number description, which reproduces the known metal-insulator transition point. The present work suggests a unified picture for various known 2D delocalization phenomena based on the same topological characterization.

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D. N. Sheng, Z. Y. Weng. 1996-09-17. A topological characterization of delocalization in a spin-orbit coupling system. https://doi.org/10.1103/physrevb.54.r11070

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