Spin Polarised Tunneling Probe for Two and Three Dimensional Dirac Metals

Abstract

One of the most promising features of the time reversal symmetry protected two and three dimensional topological band insulators lies in the fact that their surface spectrum closely mimics the spectrum of massless Dirac fermions leading to a spin-momentum locked surface state. Hence, probing this property of topological insulators in a electrical transport set up is desirable. In this article we will review the possibility of probing the spin-momentum locked nature of the surface state spectrum via spin polarized tunneling probes. We will introduce a multi-terminal avatar of TMR measurement which could lead to a direct measurement of the spin momentum locking angle and the related spin texture of the surface state spectrum.