Patent ID: 8675456

Claim:
A method of writing binary data comprising: heating a magnetic microstructure from an initial temperature to an above-ambient temperature that is not less than a transition temperature for the magnetic microstructure, wherein the magnetic microstructure comprises: a magnetic storage layer having a magnetic easy axis perpendicular to a film plane of the storage magnetic layer; a magnetic assist layer having a magnetic easy axis in the film plane; and a phase transition interlayer between the magnetic storage layer and the magnetic assist layer, wherein the phase transition interlayer comprises Fe x Rh y , wherein x+y=97 to 100 and y=49 to 52, which exhibits a first order phase transformation from an antiferromagnetic phase to a ferromagnetic phase at the transition temperature upon heating of the phase transition interlayer to the transition temperature, and wherein the phase transition interlayer magnetically exchange couples magnetic moments of the magnetic storage layer and the magnetic assist layer when the phase transition interlayer is in the ferromagnetic phase, and wherein the exchange coupling of the magnetic storage layer and the magnetic assist layer by the phase transition interlayer is greater when the phase transition interlayer is in the ferromagnetic phase than when in the antiferromagnetic phase; and reversing an orientation of magnetization of the magnetic storage layer with a magnetic field while the phase transition interlayer is in the ferromagnetic phase.