AlP and GaN are wide band gap semiconductors used industrially in light emitting diodes. We investigate their potential as tunnel barriers in magnetic tunnel junctions, employing density functional theory and the non-equilibrium Green's function method for ground state and quantum transport calculations, respectively. We show that the valence band edges are dominated by pz orbitals and the conduction band edges are dominated by s orbitals. Both materials filter Bloch states of Δ1 symmetry at the Γ-point of the Brillouin zone. In the zero bias limit, we find for the Co/AlP/Co junction a high tunnel magnetoresistance of ∼200% at the Fermi energy and for the Co/GaN/Co junction a tunnel magnetoresistance of even ∼300% about 1.4 eV below the Fermi energy.
Bibliographical noteKAUST Repository Item: Exported on 2023-09-15
Acknowledgements: The research reported in this publication was supported by funding from King Abdullah University of Science and Technology.
ASJC Scopus subject areas
- Materials Science(all)