Classical transport calculations of multilayer conductance in Co/Cu using the path-integral method

Classical transport calculations are carried out for a multilayer cobalt-co pper system, using the path-integral method. Both metals are approximated w ith free-electron descriptions, but with different mean free paths fit to t he observed bulk conductivities. These alone produce discontinuities in the slope, but not in the values, of conductance-versus-total-thickness plots. If specularity coefficients are defined for transmission at interfaces and reflection at surfaces, values different from one produce a discontinuous drop in such curves. Comparison of the calculated conductance of copper lay ers with the data of Bailey er al. [J. Appl. Phys. 85, 7345 (1999)] suggest s a specularity coefficient for reflection of some 22% and transmission of approximately 14%. This simple model can readily be extended to giant magne toresistance by assuming different specularity coefficients for spin-up and -down electrons.