We present a numerical study of conductance oscillations of transition metal
multilayers as a function of layer thickness. Using a material-specific
tight-binding model, we show that for disorder-free layers with random
thicknesses but clean interfaces, long-period oscillations in the conductance
can occur, which are reminiscent of those found in structures exhibiting GMR.
Using a heuristic effective mass model, we argue that these oscillations arise
from beating between the Fermi wavevector and a class of wavevectors
characteristic of the superlattice structure.Comment: 4 pages, 4 figure