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arXiv · 0910.3031

Anderson Impurity in Helical Metal

Xiao-Yong Feng·Wei-Qiang Chen·Jin-Hua Gao·Qiang-Hua Wang·Fu-Chun Zhang
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Abstract

We use a trial wave function to study the spin-1/2 Kondo effect of a helical metal on the surface of a three-dimensional topological insulator. While the impurity spin is quenched by conduction electrons, the spin-spin correlation of the conduction electron and impurity is strongly anisotropic in both spin and spatial spaces. As a result of strong spin-orbit coupling, the out-of-plane component of the impurity spin is found to be fully screened by the orbital angular momentum of the conduction electrons.

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Xiao-Yong Feng, Wei-Qiang Chen, Jin-Hua Gao, Qiang-Hua Wang, Fu-Chun Zhang. 2009-10-16. Anderson Impurity in Helical Metal. https://doi.org/10.1103/physrevb.81.235411

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