Patent ID: 8213221

Claim:
A device, comprising: a magnetic cell comprising: a first ferromagnetic layer exhibiting a first magnetization that is switchable between a first direction and a second substantially opposite direction under a spin-transfer torque effect caused by an electric current; a second ferromagnetic layer having a fixed magnetization in one of the first and second directions; and a non-magnetic spacer layer formed between the first and second ferromagnetic layers to allow for passage of the electric current between the first and second ferromagnetic layers; a magnetic shielding layer to overlay the magnetic cell on one side of the magnetic cell and operable to magnetically shield the magnetic cell from an external magnetic field, the magnetic shielding layer being electrically conductive and comprising a magnetic material that exhibits a positive susceptibility under the external magnetic field; and a circuit electrically coupled to the magnetic shielding layer and the magnetic cell to supply the electric current flowing perpendicularly to and through the magnetic shielding layer and the magnetic cell.