Control device for reversing the direction of magnetisation without an external magnetic field

A device for controlling magnetization reversal of a ferromagnetic device without using an external magnetic field, comprising:

• at least two flat electrodes;
• a magnetic control part between said two flat electrodes including, starting from the first electrode, a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer, and a second electrode, the thickness of said second ferromagnetic layer being less than that of said first layer, and the thickness of said second electrode being sufficiently small to enable magnetic coupling between said second ferromagnetic layer and a controlled ferromagnetic device controlled by the control device wherein said first and second ferromagnetic layer are entirely metallic and electrically conductive;
• and
• a controlled device in contact with one of the two electrodes such that the sum of the thicknesses of the electrode and the controlled device is less than a predefined value E corresponding to the limiting distance between the second ferromagnetic layer and the controlled device, the value E being beyond which the controlled device can no longer induce magnetization reversal in the controlled device.