Electron tunneling through a single magnetic barrier in HgTe topological insulator

TL;DR

This paper theoretically investigates electron tunneling in HgTe topological insulators with a magnetic barrier, revealing control mechanisms for edge state transport and potential for nanoelectronic device applications.

Contribution

It demonstrates how magnetic fields and Fermi energy tuning can switch topological edge channels on and off, enabling spin-polarized current control in HgTe topological insulators.

Findings

Magnetic field does not induce spin-flip in edge states due to angular momentum conservation.

Edge channels can be switched from conductive to insulating states by tuning magnetic field and Fermi energy.

Current can be fully spin-polarized, enabling spintronic applications.

Abstract

Electron tunneling through a single magnetic barrier in a HgTe topological insulator has been theoretically investigated. We find that the perpendicular magnetic field would not lead to spin-flip of the edge states due to the conservation of the angular moment. By tuning the magnetic field and Fermi energy, the edge channels can be transited from switch-on states to switch-off states and the current can be transmitted from unpolarized states to totally spin polarized states. These features offer us and efficient way to control the topological edge state transport, and pave a way to construct the nanoelectronic devices utilizing the topological edge states.