Abstract: The disclosure relates to a device for controlling magnetization reversal in a controlled ferromagnetic system such as a magnetic memory element, without using an external magnetic field, wherein it comprises between two flat electrodes a magnetic control part comprising, starting from the first electrode, a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer, and the second of said two flat electrodes, 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 the system controlled by the control device.

Abstract: The disclosure relates to a device for controlling magnetization reversal in a controlled ferromagnetic system such as a magnetic memory element, without using an external magnetic field, wherein it comprises between two flat electrodes a magnetic control part comprising, starting from the first electrode, a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer, and the second of said two flat electrodes, 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 the system controlled by the control device.

Abstract: A magnetic sensor having a layer of nonmagnetic insulator including at least one layer of ferromagnetic particles. This combination of layers is sandwiched between two ferromagnetic electrodes. Electrons are transported by the tunneling effect between each electrode and the ferromagnetic particles. The tunneling resistance depends on the orientation of the magnetization of the electrodes and therefore varies in the presence of the magnetic field. The multichannel and multistage nature of the tunneling conduction eliminates the problems of short-circuiting by porosity, thus leading to less difficult fabrication and improved robustness in terms of breakdown. The possible thermal fluctuations of the magnetic moments of the aggregates can be suppressed by the choice of a magnetic material for the part of the insulating layer which contains the aggregates.