2-Dimensional To 3-Dimensional Recoupling In Agmn/Cu Multilayers

The return from "quasi-two-dimensional" to three-dimensional (3D) behavior of the spin-glass Ag0.91Mn0.09 is studied in multilayer samples of Ag-Mn layers of width 4 nm alternated with Cu interlayers of width 1 nm less-than-or-equal-to W(il) less-than-or-equal-to 60 nm. For W(il) > 30 nm, the SG layers are magnetically decoupled; as W(il) decreases below 30 nm, the quasistatic spin-freezing temperature T(f) gradually rises toward the bulk spin-freezing temperature T(f)b. When normalized to T(f)/T(f)b, the Ag-Mn data increase with decreasing W(il) in a fashion similar to previous data for Cu-Mn. The data are compared with three different equations.