Application of the Point-Like Contact Model: Resistance Oscillations of the Domain Wall in Magnetic Nanowires and Junctions Due to Mean Free Path Effects

Abstract

This work is focused on determining the electrical resistance, which is induced by single domain wall (DW) in magnetic nanowire (NW) with a negligible defect. The provided model covers a wide range of NW diameters. The obtained result demonstrates a few-order rapid reduction of the DW resistance accompanied by its possible deviations versus the diameter growth ranging from 1.2[Formula: see text]nm to 15.2[Formula: see text]nm. The origin of these deviations, which are also identified as oscillations, is referred to the nonuniform electron scattering on the DW due to the intermixing electron scattering conditions: ballistic for one spin channel and quasi-ballistic for other one with opposite spin direction. It may happen when the DW width by value is approximately in between two lengths: a mean free path (MFP) with the spin down and spin up. The indirect evidence of this finding also comes from the fact that homogeneous NWs show the most valuable DW resistance oscillations by magnitude rather than segmented magnetic NWs. In addition to the approach, where DW width is constant, the other reasonable model is used when the DW can be constrained for some conditions. The same results are valid for magnetic junctions with DW. Finally, resistance simulation in the diffusive range, when a diameter of the NW (or point-like junction) is larger than any of spin-resolved MFP of electrons, successfully follows experimental data for the single and double DW resistances available in literature.