US Patent 7813164 Magneto resistance element and magnetic random access memory

A magneto-resistance element includes a free layer, a fixed layer and a non-magnetic layer interposed between the free layer and the fixed layer. The free layer has a first magnetic layer, a second magnetic layer, a third magnetic layer, a first non-magnetic layer interposed between the first magnetic layer and the second magnetic layer, and a second non-magnetic layer interposed between the second magnetic layer and the third magnetic layer. The first magnetic layer, the second magnetic layer and the third magnetic layer are coupled such that spontaneous magnetizations have a helical structure.