Condensed Matter Physics Seminar
Magnetization dynamics induced by spin-polarized currents
University of Missouri-Columbia
In magnetoelectronics (or spintronics), one is often interested in how magnetization configurations determine spin-dependent transport. The reverse effect, namely, the spin-polarized current controls magnetization patterns, receives an increasing attention in the magnetoelectronics community. When a spin-polarized current is injected into a ferromagnetic material, the background magnetization receives a spin torque. We have found that the current-induced spin torque has many unique properties. Among them, we demonstrate, by explicitly solving the modified Landau-LiftshitzGilbert equation, that the spin torque distorts domain structures, drives domain walls out of equilibrium, makes magnetization switching from one direction to another, and creates spin excitations. We also describe the technological relevance of the spin torque for magnetoresistive reading heads in disc drives and for magnetic random access memory.
Thursday, October 30, 2003
Gant Science Complex
(The seminar is followed by coffee/tea, cookies, and an informal discussions.)