The influence of a spin polarized electric current on the magnetization configuration of nanostructures.

Recently, there has been a surge of interest in the spin-torque transfer or STT-effect [3]. In this case a spinpolarized electron current is transported through a ferromagnetic layer in such a way that the electron spin and the magnetization of the ferromagnetic layer are not collinear. This can, for instance, be realized by using another ferromagnetic layer as injector with a magnetization directions that is different from that in the free layer. The electrons get polarized in the injector layer and transfer a fraction of their spin angular moment to the second ferromagnetic layer, thereby changing the magnetization configuration of the second layer (in a sense the opposite of GMR). The STT-effect has been theoretically predicted in 1996, and was observed experimentally around 2000. In this project we suggest to study the STT-effect in three types of structures: (i) thin ferromagnetic films with lateral patterning, (ii) films with embedded ferromagnetic nanoprecipitates; (iii) multilayer structures for vertical electron transport.

Keywords:nanostructures, magnetism, spin torque, current-induced reversal

Disciplines:Condensed matter physics and nanophysics