Artificial antiferromagnets

Artificial antiferromagnets are thin-film stacks with alternating layers of a ferromagnet such as cobalt and a nonmagnetic metal such as copper or ruthenium which serves to provide magnetic coupling from one ferromagnetic layer to the next. The structure can be reduced to a three-layer sandwich. Now M_α is the magnetization of the ferromagnetic layer, and μ₀Hⁱ_α represents the interlayer coupling. Typically μ₀Hⁱ_α and μ₀H_a are of order 1 T, so the spin-flop field μ₀H_sf is similar in magnitude. Artificial antiferromagnets are used in spin-valve structures