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Transmission of correlated electrons through sharp domain walls in magnetic nanowires: a renormalization group approach

M. A. N. Araujo·V. K. Dugaev·V. R. Vieira·J. Berakdar·J Barnas
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Abstract

The transmission of correlated electrons through a domain wall in a ferromagnetic one dimensional system is studied theoretically in the limit of a domain wall width smaller or comparable to the electron Fermi wavelength. The domain wall gives rise to both potential and spin dependent scattering of the charge carriers. Using a poor man's renormalization group approach for the electron-electron interactions, we obtain the low temperature behavior of the reflection and transmission coefficients. The results show that the low-temperature conductance is governed by the electron correlations, which may suppress charge transport without suppressing spin current. The results may account for a huge magnetoresistance associated with a domain wall in ballistic nanocontacs.

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M. A. N. Araujo, V. K. Dugaev, V. R. Vieira, J. Berakdar, J Barnas. 2006-10-09. Transmission of correlated electrons through sharp domain walls in magnetic nanowires: a renormalization group approach. https://doi.org/10.1103/physrevb.74.224429

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