Patent ID: 8675316

Claim:
A magnetic head, comprising: a magnetoresistive read sensor including a free layer, a barrier layer and a pinned structure between the barrier layer and an antiferromagnetic pinning layer, the pinned structure comprising: a first pinned layer exchange coupled to the antiferromagnetic pinning layer; an antiparallel coupling layer; and a second pinned stack disposed between the barrier layer and the antiparallel coupling layer and antiparallel coupled to the first pinned layer, wherein the second pinned stack includes a compositionally distinct separation layer between and contacting a second pinned layer and a sub-second pinned layer, the compositionally distinct separation layer is of such a thickness and material composition as to parallel couple the second pinned layer and the sub-second pinned layer such that the second pinned layer and the sub-second pinned layer are magnetized in the same direction.