Pseudospin-valve effect on transport in junctions of three-dimensional topological insulator surfaces

Abstract

We show that the surface states of pristine 3D topological insulators (TIs) are analogs of ferromagnetic half metals due to complete polarization of an emergent momentum independent pseudospin (SU(2)) degree of freedom on the surface. To put this claim on firm footing, we present results for TI surfaces perpendicular to the crystal growth axis, which clearly show that the tunneling conductance between two such TI surfaces of the same TI material is dominated by this half metallic behavior leading to physics reminiscent of a spin-valve. Further using the generalized tunnel magnetoresistance derived in this work we also study the tunneling current between arbitrary TI surfaces. We also perform a comprehensive study of the effect of all possible surface potentials allowed by time reversal symmetry on this spin-valve effect and show that it is robust against most of such potentials.

11 pages, 5 figures, 1 table, version published in New Journal of Physics

References in corpus (5)

• Surface State Magnetization and Chiral Edge States on Topological Insulators
• Mapping the unconventional orbital texture in topological crystalline insulators
• Edge states of a three-dimensional topological insulator
• Transport signatures of surface potentials on three-dimensional topological insulators
• Probing surface states exposed by crystal terminations at arbitrary orientations of three-dimensional topological insulators

Cited by in corpus (2)

• Jackiw-Rebbi zero modes in non-uniform topological insulator nanowire
• Robust Majorana bound state in pseudo-spin domain wall of 2-D topological insulator