Patent ID: 8391056

Claim:
A magnetic storage device comprising: a network of flat magnetic cells on a substrate, the dimensions of each magnetic cell being chosen such that the cell is in a vortex state, a vortex core of each cell having a magnetization with a first and second equilibrium position in the opposite direction and roughly perpendicular to a plane of said cell, each of said two positions representing a piece of binary information; means for writing binary information stored in the cells, said means of writing including means for selectively and simultaneously applying the following in the vicinity of each cell: a first static magnetic field with roughly perpendicular bias to said plane; a radio frequency magnetic field with linear polarization, including two right and left circular polarization roughly parallel to said plane, such that: a simultaneous application of said first static magnetic field and said radio frequency magnetic field at a first frequency on the selected cell causes: a switch in the magnetization direction of said vortex core located in the first equilibrium position toward the second equilibrium position under the effect of a circular movement of the core around said first equilibrium position, causing the reversal in the magnetization, said vortex core rotating by being coupled to one of the two circular polarizations; the maintenance of the magnetization direction of said vortex core located in the second equilibrium position; a simultaneous application of said first static magnetic field and said radio frequency magnetic field at a second frequency that is different than said first frequency on the selected cell causes: a switch in the magnetization direction of said vortex core located in the second equilibrium position toward the first equilibrium position under the effect of a circular movement of said core around said second equilibrium position, causing the reversal in the magnetization, said vortex core rotating by being coupled to one of the two circular polarizations; the maintenance of the magnetization direction of said vortex core located in the first equilibrium position.