GMR IN MAGNETIC MULTILAYERS FROM A FIRST PRINCIPLES BAND-STRUCTURE KUBO-GREENWOOD APPROACH

We employ the Kubo-Greenwood formula to investigate from first-princip les the giant magnetoresistance in FemMn (M=V, Cr, Mn and Cu) superlat tices. The results indicate that MR can arise from band structure chan ges from ferromagnetic to anti-ferromagnetic alignments. Quantum confi nement in the perpendicular direction is induced by the potential step s between the Fe and spacer layers and causes a much larger MR in the current-perpendicular-to-the-plane (CPP) geometry than in the current- inplane (CIP) geometry. In the presence of the spinorbit coupling inte raction, MR is found to be reduced by spin-channel mixing.