Structural relaxation effects on interface and transport properties of Fe/MgO(001) tunnel junctions

Abstract

The interface structure of Fe/MgO(100) magnetic tunnel junctions predicted by density functional theory (DFT) depends significantly on the choice of exchange and correlation functional. Bader analysis reveals that structures obtained by relaxing the cell with the local spin-density approximation (LSDA) display a different charge transfer than those relaxed with the generalized gradient approximation (GGA). As a consequence, the electronic transport is found to be extremely sensitive to the interface structure. In particular, the conductance for the LSDA-relaxed geometry is about one order of magnitude smaller than that of the GGA-relaxed one. The high sensitivity of the electronic current to the details of the interface might explain the discrepancy between the experimental and calculated values of magnetoresistance.

Submitted to PRL, 5 figures

References in corpus (4)

• The SIESTA method for ab initio order-N materials simulation
• Efficient index handling of multidimensional periodic boundary conditions
• Magnetic Moment Collapse-Driven Mott Transition in MnO
• Resonant electronic states and I-V curves of Fe/MgO/Fe(100) tunnel junctions

Cited by in corpus (6)

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• Anisotropic carrier dynamics in a laser-excited Fe${}_1$/(MgO)${}_3$(001) heterostructure from real-time time-dependent DFT
• Strength of the symmetry spin filtering effect in magnetic tunnel junctions
• Taming the resistive switching in Fe/MgO/V/Fe magnetic tunnel junctions: An ab initio study