Shadow Bands and Tunneling Magnetoresistance in Itinerant Electron Ferromagnets

A. H. MacDonald; T. Jungwirth; M. Kasner

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Shadow Bands and Tunneling Magnetoresistance in Itinerant Electron Ferromagnets

A. H. MacDonald·T. Jungwirth·M. Kasner

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Abstract

In itinerant electron ferromagnets spectral weight is transferred at finite temperatures from quasiparticle peaks located at majority and minority-spin band energies to shadow-band peaks. For a given Bloch wavevector and band index, the majority-spin shadow-band peak is located near the minority-spin quasiparticle energy and the minority-spin shadow-band peak is located near the majority-spin quasiparticle energy. This property can explain much of the temperature dependence seen in the magnetoresistance of magnetic tunnel junctions.

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A. H. MacDonald, T. Jungwirth, M. Kasner. 1998-01-05. Shadow Bands and Tunneling Magnetoresistance in Itinerant Electron Ferromagnets. https://arxiv.org/abs/cond-mat/9801023

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