SPIN-VALVE ELEMENT DRIVING METHOD, AND SPIN-VALVE ELEMENT

摘要

Disclosed are a spin-valve element, in which a pair of ferromagnetic layers have different coercive forces so that the spin-valve element may be driven to oscillate microwaves with a weakened external magnetic field or no external magnetic field being applied, and a spin-valve element driving method for acquiring an electromagnetic signal from the spin-valve element. A stationary layer or a ferromagnetic layer having a higher coercive force of the paired ferromagnetic layers is magnetized substantially normal to the film face of the stationary layer, so that an electric current flows from one of the paired ferromagnetic layers to the other through an intermediate layer. At this driving time, a set of the value of the magnitude of the external magnetic field and the value of the electric current to be fed to the spin-valve element is made to satisfy a predetermined condition. Of the paired ferromagnetic layers, alternatively, the free layer or the ferromagnetic layer having a lower coercive force is made to have the physical property capable of realizing that condition.