MULTI-VALUED DATA RECORDING SPIN INJECTION MAGANETIZATION REVERSAL ELEMENT AND DEVICE USING THE ELEMENT

摘要

A spin injection magnetization reversal device is disclosed which inhibits an increase in resistance to enable multi-valued data recording. A ferromagnetic fixed layer and n groups each including a ferromagnetic free layer and an isolation layer are disclosed. The groups are disposed from the group including the first ferromagnetic free layer provided on the ferromagnetic fixed layer to the group including the n-th ferromagnetic free layer in the order. Each of the ferromagnetic free layers is preferably formed of one of a CoCrPt alloy, a CoCr alloy and a CoPt alloy with Pt or Cu concentration therein made monotonically decreased from the concentration in the first ferromagnetic free layer to that in the n-th ferromagnetic free layer.