An approximate calculation for transport in magnetic tunnel junctions in the presence of localized states

Peter M. Levy, Kuising Wang, Peter H. Dederichs, Carsten Heide, Shufeng Zhang, L. Szunyogh

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

In conventional calculations of transport in magnetic tunnel junctions, one usually assumes that the transverse momentum of the tunnelling electrons is conserved and that the itinerant electron states are orthogonal to localized states. However, in most of the junctions studied, there is diffuse scattering in both the bulk of the electrodes and the barrier so that the transverse momentum is not conserved, and there are processes that couple localized states at the electrode-barrier interface to the itinerant states in the bulk of the electrodes. While it is in principle possible to include these effects, it leads to lengthy calculations. Here we propose an approximate scheme in which we do not take explicit account of either of the effects mentioned above, but in which we calculate the tunnelling through all the states that exist at the electrode-barrier interfaces. We compare the k∥-resolved density of states and tunnelling currents across a junction in our approximate scheme with that found using the Landauer formalism in the ballistic limit.

Original languageEnglish
Pages (from-to)763-769
Number of pages7
JournalPhilosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties
Volume82
Issue number7
DOIs
Publication statusPublished - May 10 2002

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Tunnel junctions
tunnel junctions
Electrodes
electrodes
transverse momentum
Momentum
Electron tunneling
Ballistics
electron tunneling
electron states
Electron energy levels
ballistics
Scattering
formalism
scattering

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Physics and Astronomy(all)

Cite this

An approximate calculation for transport in magnetic tunnel junctions in the presence of localized states. / Levy, Peter M.; Wang, Kuising; Dederichs, Peter H.; Heide, Carsten; Zhang, Shufeng; Szunyogh, L.

In: Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties, Vol. 82, No. 7, 10.05.2002, p. 763-769.

Research output: Contribution to journalArticle

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