Electrical Detection of the Helical Spin Texture in a p-type Topological Insulator Sb2Te3.

ABSTRACT: The surface states of 3D topological insulators (TIs) exhibit a helical spin texture with spin locked at right angles with momentum. The chirality of this spin texture is expected to invert crossing the Dirac point, a property that has been experimentally observed by optical probes. Here, we directly determine the chirality below the Dirac point by electrically detecting spin-momentum locking in surface states of a p-type TI, Sb2Te3. A current flowing in the Sb2Te3 surface states generates a net spin polarization due to spin-momentum locking, which is electrically detected as a voltage on an Fe/Al2O3 tunnel barrier detector. Measurements of this voltage as a function of current direction and detector magnetization indicate that hole spin-momentum locking follows the right-hand rule, opposi

SUBMITTER: Li CH 

PROVIDER: S-EPMC4941728 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature