Spin-filter magnetoresistance in magnetic barrier junctions

TL;DR

This paper explores how spin-filter barriers influence tunnel magnetoresistance in magnetic junctions, revealing that TMR depends on magnetic alignment and voltage, with potential implications for spintronic devices.

Contribution

It introduces a theoretical analysis of spin-filter effects on TMR using transfer matrix method and free-electron approximation, highlighting the dependence on magnetic orientation and voltage.

Findings

TMR increases with applied voltage.

Maximum tunnel current occurs when magnetic moments are parallel.

Spin transport depends on relative magnetization orientation.

Abstract

The tunnel current and magnetoresistance (TMR) are investigated in magnetic tunnel junctions consisting of a spin-filter tunnel barrier, sandwiched between a ferromagnetic (FM) electrode and a nonmagnetic (NM) electrode. The investigations are based on the transfer matrix method and the free-electron approximation. The numerical results show that the spin transport depends on the relative magnetization orientation of the FM electrode and the spin-filter barrier, such that the tunnel current reaches its maximum when the magnetic moments of the FM electrode and the magnetic barrier are parallel. It is also found that the TMR increases with increasing the applied voltage.