Perpendicular-current Studies of Electron Transport Across Metal/Metal Interfaces

摘要

We review what we have learned about the scattering of electrons by theinterfaces between two different metals (M1/M2) in thecurrent-perpendicular-to-plane (CPP) geometry. In this geometry, the intrinsicquantity is the specific resistance, AR, the product of the area through whichthe CPP current flows times the CPP resistance. We describe results for bothnon-magnetic/non-magnetic (N1/N2) and ferromagnetic/non-magnetic (F/N) pairs.We focus especially upon cases where M1/M2 are lattice matched (i.e., have thesame crystal structure and the same lattice parameters to within ~ 1%), becausein these cases no-free-parameter calculations of 2AR agree surprisingly wellwith measured values. But we also list and briefly discuss cases where M1/M2are not lattice matched, either having different crystal structures, or latticeparameters that differ by several percent. The published calculations of 2AR inthese latter cases do not agree so well with measured values.