A method of controlling a magnetization easy axis of a ferromagnetic film,
an ultrahigh-density, low power, nonvolatile magnetic memory using the
control method, and a method of writing information on the magnetic
memory. The method includes the step of arranging an electrode layer, a
piezoelectric layer and a magnetic layer in a layered structure. Voltage
is applied to the electrode layer to generate an electric field.
Thereafter, lattice change is caused in the piezoelectric layer using the
generated electric field. A magnetization easy axis of the magnetic layer
is reversibly switched between in-plane and out-of-plane by exerting
stress generated by the lattice change onto the magnetic layer.
