Prior measurements of the current perpendicular to the layer planes (C
PP) resistances, taken on Co/Cu/Py/Cu (Py=Ni84Fe16 multilayers with a
single pair of Co and Py thicknesses, are extended to three additional
pairs of thicknesses. The same parameters, obtained from independent
measurements on Co/Cu and Py/Cu multilayers that fit the original pair
reasonably well, fit the three new pairs almost as well, from which w
e conclude that there is substantial predictability in the CPP magneto
resistance (MR). Because the predictability is not perfect, we examine
the extent to which we can improve the fits to the Co/Cu/Py/Cu data b
y varying the Py/Cu and Co/Cu parameters within their uncertainties, w
ithout substantially weakening the fits to the original Co/Cu and Py/C
u data. We conclude by presenting the first CPP-MR measurements on Co/
Ag/Py/Ag multilayers. The data are similar to those for Co/Cu/Py/Cu mu
ltilayers, but the Co/Ag/Py/Ag MRs are noticeably larger. (C) 1996 Ame
rican Institute of Physics.