Electron transport in magnetic tunnel junctions -- a theoretical study of lattice and continuum models

TL;DR

This paper compares lattice and continuum models of magnetic tunnel junctions, revealing discrepancies in conductance calculations under high Zeeman fields and proposing a resolution for the modeling approach.

Contribution

It introduces a method to reconcile lattice and continuum models for magnetic tunnel junctions, improving the accuracy of conductance predictions.

Findings

Discrepancy in conductance between models at large Zeeman fields

Mapping between lattice and continuum models reveals differences

Proposed modeling approach resolves the discrepancy

Abstract

Magnetic tunnel junctions comprising of an insulator sandwiched between two ferromagnetic films are the simplest spintronic devices. Theoretically, these can be modeled by a metallic Hamiltonian in both the lattice and the continuum with an addition of Zeeman field. We calculate conductance at arbitrary orientations of the easy axes of the two ferromagnets. When mapped, the lattice and the continuum models show a discrepancy in conductance in the limit of a large Zeeman field. We resolve the discrepancy by modeling the continuum theory in an appropriate way.