A high speed and low power method to control and switch the magnetization
direction and/or helicity of a magnetic region in a magnetic device for
memory cells using spin polarized electrical current. The magnetic device
comprises a reference magnetic layer with a fixed magnetic helicity
and/or magnetization direction and a free magnetic layer with a
changeable magnetic helicity. The fixed magnetic layer and the free
magnetic layer are preferably separated by a non-magnetic layer, and the
reference layer includes an easy axis perpendicular to the reference
layer. A current can be applied to the device to induce a torque that
alters the magnetic state of the device so that it can act as a magnetic
memory for writing information. The resistance, which depends on the
magnetic state of the device, is measured to thereby read out the
information stored in the device.