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The theory of GMR and TMR in segmented magnetic nanowires

M. Ye. Zhuravlev·H. O. Lutz·A. V. Vedyayev
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Abstract

We calculate the resistivity and Giant Magnetoresistance (GMR) of a segmented nanowire consisting of two ferromagnetic segments separated by a thin paramagnetic spacer. The quantization of the electron motion due to the small nanowire cross-section is taken into account; s-d electron scattering gives rise to different mean free paths for spin-up and spin-down s-electrons. The calculated resistivity and GMR oscillate as a function of nanowire cross-section due to the difference in Fermi momenta of d-electrons with opposite spins. The GMR can reach values much higher than those which are obtained for "wires" of infinite cross-section (i.e., a multilayer). Similarly we have calculated the Tunneling Magnetoresistance (TMR) by replacing the paramagnetic spacer with an insulator spacer.

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M. Ye. Zhuravlev, H. O. Lutz, A. V. Vedyayev. 2000-02-21. The theory of GMR and TMR in segmented magnetic nanowires. https://arxiv.org/abs/cond-mat/0002325

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