Size effects in the giant magnetoresistance of segmented nanowires - art. no. 174409

We calculate the resistivity and giant magnetoresistance (GMR) of a segment ed nanowire consisting of two ferromagnetic segments separated by a thin pa ramagnetic spacer. Spin-dependent surface electron scattering is taken into account. The quantization of the electron motion due to the small nanowire cross section leads to oscillations of the resistivity and the GMR. The in terplay between spin-dependent electron scattering in the bulk and the surf ace results ina complex behavior of the GMR as a function of nanowire radiu s and surface-potential strength. Both increase and decrease of the GMR can be obtained as the spin-dependent surface scattering grows.