STUDY OF GIANT MAGNETORESISTANCE IN CO X SUPERLATTICES (X = CU, RU, RH AND PD) BY FIRST-PRINCIPLE BAND CALCULATION/

First-principle band structure calculation based on linear-muffin-tin- orbital atomic-sphere-approximation method is used to study the giant magnetoresistance (MR) effect and the electronic structure of Co/X sup erlattices (X = Cu, Ru, Rh and Pd). The MR ratio is estimated as the r atio of the D(epsilon(F))upsilon(F)(2) between the anti-parallel and t he parallel magnetic configurations, where D(epsilon(F)) and upsilon(F ) are the density of states at Fermi energy and the Fermi velocity. Th e non-magnetic layer thickness dependence of the MR ratio is also calc ulated. These results are in good agreement with experiments. (C) 1998 Elsevier Science B.V. All rights reserved.