Spin-polarized current-induced magnetization precession and switching for perpendicular anisotropic ferrimagnetic thin films

Abstract

We present here a theoretical calculation on magnetization precession and switching induced by spin-polarized current spin-transfer torque using perpendicular anisotropic magnetic multilayered thin films which contain two strongly coupled antiparallel magnetic subnetworks. We develop a modified Landau-Lifshitz-Gilbert equation for this material structure to obtain the final equation governing the dynamics of the net magnetization. We present results of the time evolution of the net magnetization under the influence of a spin current as well as the estimation of the critical current for practical application in magnetic random access memory writing. A relation between magnetization switching time and current is also given.

Influence of a periodic magnetic field and spin-polarized current on the magnetic dynamics of a monodomain ferromagnet

“…Ringing can occur both in the vicinity of the easy plane 16 or cover the entire unitary sphere. 17,18 Use of ac currents 19 and fields allows to suppress the ringing in different degrees, thus achieving magnetization switching on the timescale of dozens of picoseconds. [20][21][22] The macrospin switching along the shortest trajectory, socalled "ballistic 23 magnetization reversal" ͑BMR͒, in the ideal case takes place along a meridian of the unitary sphere.…”