We developed a parametrization of transmission probability that reliably captures essential elements of the tunneling process in magnetic tunnel junctions. The electronic structure of Fe/MgO system is calculated within the quasiparticle self-consistent GW approximation and used to evaluate transmission probability across (001) Fe/MgO interface. The transmission has a peak at +0.12 V, in excellent agreement with recent differential conductance measurements for electrodes with antiparallel spin. These findings confirm that the observed current-voltage characteristics are intrinsic to well defined (001) Fe/MgO interfaces, in contrast to previous predictions based on the local spin-density approximation, and also that many-body effects are important to realistically describe electron transport across well defined metal-insulator interfaces.
@article{arxiv.1010.4086,
title = {Effect of electron correlations on (001) Fe/MgO interfaces},
author = {Sergey V. Faleev and Oleg N. Mryasov and Mark van Schilfgaarde},
journal= {arXiv preprint arXiv:1010.4086},
year = {2012}
}