Effects of structural relaxation on calculations of the interface and transport properties of Fe/MgO(001) tunnel junctions
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2009Access:
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X.Feng, O. Bengone, M. Alouani, S. Leb`egue, I. Rungger, and S. Sanvito, Effects of structural relaxation on calculations of the interface and transport properties of Fe/MgO(001) tunnel junctions, Phys. Rev. B, 79, 2009, 174414Download Item:
Abstract:
The relaxation of the interface structure of Fe/MgO
100
magnetic tunnel junctions predicted by density-
functional theory 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 con-
sequence, the electronic transport is found to be extremely sensitive to the interface structure. In particular, the
conductance for the LSDA-relaxed geometry is about 1 order of magnitude smaller than that of the GGA-
relaxed one. Surprisingly, the effect of the exchange and correlation potential within both the LSDA and the
GGA has a little effect on the calculated transmission coefficient when applied to the same Fe/MgO/Fe
001
geometry. The high sensitivity of the electronic current to the details of the relaxed interface might explain the
discrepancy between the experimental and calculated values of magnetoresistance
Sponsor
Grant Number
Science Foundation Ireland (SFI)
07/RFP/PHYF235
Science Foundation Ireland (SFI)
07/IN.1/I945
Author's Homepage:
http://people.tcd.ie/sanvitosDescription:
PUBLISHED
Author: RUNGGER, IVAN; SANVITO, STEFANO
Sponsor:
Science Foundation Ireland (SFI)Science Foundation Ireland (SFI)
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Series/Report no:
Phys. Rev. B79
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Full text availableKeywords:
density-functional theorySubject (TCD):
Nanoscience & MaterialsDOI:
http://dx.doi.org/10.1103/PhysRevB.79.174414Metadata
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