Electron transport in a ferromagnetic/normal/ferromagnetic tunnel junction based on the surface of a topological insulator

TL;DR

This paper theoretically investigates electron transport in a topological insulator-based ferromagnetic/normal/ferromagnetic junction, revealing tunable conductance, magnetoresistance effects, and Fabry-Perot-like interference, with implications for spintronics.

Contribution

It introduces a theoretical model of electron transport in a topological insulator junction, highlighting tunable conductance and magnetoresistance effects not previously detailed.

Findings

Conductance is higher in parallel than antiparallel magnetic configurations.

Gate voltage can tune phase shifts affecting conductance.

Fabry-Perot-like electron interference observed.

Abstract

We theoretically study the electron transport properties in a ferromagnetic/normal/ferromagnetic tunnel junction, which is deposited on the top of a topological surface. The conductance at the parallel (\textbf{P}) configuration can be much bigger than that at the antiparallel (\textbf{AP}) configuration. Compared \textbf{P} with \textbf{AP} configuration, there exists a shift of phase which can be tuned by gate voltage. We find that the exchange field weakly affects the conductance of carriers for \textbf{P} configuration but can dramatically suppress the conductance of carriers for \textbf{AP} configuration. This controllable electron transport implies anomalous magnetoresistance in this topological spin valve, which may contribute to the development of spintronics . In addition, we find that there is a Fabry-Perot-like electron interference.