J. Inoue, EFFECTS OF BULK AND INTERFACE SCATTERING ON GIANT MAGNETORESISTANCE IN MAGNETIC MULTILAYERS, Journal of magnetism and magnetic materials, 164(3), 1996, pp. 273-283
The effects on the giant magnetoresistance (GMR) of various types of r
andomness in magnetic multilayers are studied using a simple two-band
(s + d) model for FM/Cu/FM-type trilayers, where FM is the ferromagnet
ic metal or alloy. Three types of randomness: (i) spin-independent ran
domness, (ii) spin-dependent bulk and (iii) spin-dependent interface r
andomness, are taken into account to calculate CIP (current in plane t
o layers) GMR. The conductivity is calculated in the Kubo formalism. I
t is shown that the dependence of GMR on the spin-independent randomne
ss is rather strong and that both bulk and interface randomness contri
bute to GMR in permalloy/Cu-type multilayers. Based on the calculated
results, we analyze the concentration dependence of the GMR of Co-Ni/C
u multilayers and find that the interface randomness governs the basic
feature of the concentration dependence of GMR in these multilayers.
The other types of randomness, however, are necessary to obtain quanti
tative agreement between the experimental and theoretical values of th
e MR ratio. The implications of GMR effects observed in amorphous FM/C
u multilayers are also presented.