Spin-Charge Locking and Tunneling into a Helical Metal

Abstract

We derive a kinetic equation for the electrons moving on the surface of a three-dimensional topological insulator. Due to the helical nature of the excitations backward scattering is suppressed in the collision integral, and the spin dynamics is entirely constrained by that of the charge. We further analyze the tunneling between the helical and a conventional metal or ferromagnet. We find that the tunnel resistance strongly depends on the angle between the magnetization in the ferromagnet and the current in the helical metal. A nonmagnetic layer on top of the helical metal amplifies the current-induced spin polarization.

5 pages, 1 figure

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Cited by in corpus (6)

• Optimal charge-to-spin conversion in graphene on transition metal dichalcogenides
• Magnetoelectrics in Disordered Topological Insulator Josephson Junctions
• Weak Localization and Antilocalization in Topological Materials with Impurity Spin-Orbit Interactions
• Quantum Transport in Weyl Semimetal Thin Films in the Presence of Spin-Orbit Coupled Impurities
• Hot-carrier transport and spin relaxation on the surface of topological insulator
• Theory of magnetotransport in shaped topological insulator nanowires