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Nonmonotonic inelastic tunneling spectra due to surface spin excitations in ferromagnetic junctions

G. Tkachov
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Abstract

The paper addresses inelastic spin-flip tunneling accompanied by surface spin excitations (magnons) in ferromagnetic junctions. The inelastic tunneling current is proportional to the magnon density of states which is energy-independent for the surface waves and, for this reason, cannot account for the bias-voltage dependence of the observed inelastic tunneling spectra. This paper shows that the bias-voltage dependence of the tunneling spectra can arise from the tunneling matrix elements of the electron-magnon interaction. These matrix elements are derived from the Coulomb exchange interaction using the itinerant-electron model of magnon-assisted tunneling. The results for the inelastic tunneling spectra, based on the nonequilibrium Green's function calculations, are presented for both parallel and antiparallel magnetizations in the ferromagnetic leads.

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G. Tkachov. 2011-08-23. Nonmonotonic inelastic tunneling spectra due to surface spin excitations in ferromagnetic junctions. https://doi.org/10.1140/epjb%2Fe2011-20271-2

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