Anderson Localization at the Edge of a 2D Topological Insulator
11.10.2013 at 10:15
Spins of chiral electrons moving along the 1D helical edge of a 2D topological insulator are tightly bound to their momenta. This suppresses electron backscattering by the usual potential disorder and protects the system from Anderson localization. We study effects of electron interactions with a disordered chain of spin (Kondo) impurities located near the helical edge. Assuming the electron-spin couplings of random anisotropies, we map this system to the problem of the pinning of the charge density wave by the disordered potential. This mapping proves that an arbitrary weak anisotropic disorder in coupling of chiral electrons with spin impurities leads to the Anderson localization of the helical edge states .
 B.L. Altshuler, I.L. Aleiner, and V.I. Yudson, Phys. Rev. Lett. 111, 086401 (2013).
A348 - Theresienstr. 37