Electrical detection of magnetization dynamics in an ultrathin CoFeB film with perpendicular anisotropy

The anomalous Hall effect (AHE) was used to investigate the magnetization dynamics of an ultrathin (1.3  nm) CoFeB magnetic multilayer with perpendicularmagnetic anisotropy (PMA). By directly sending a radio frequency (rf)current into a millimeter-sizedfilm sample without any lithography process, aresonantdc voltage can be detected along the Hall direction. This method was used to study the dynamic properties of ultrathin CoFeBfilms, such as the gyromagnetic ratio, amplitude of PMA field, and magnetic damping. Thedc voltage was proven to be the consequence of spinrectification enabled by the AHE, and the dynamic magnetization was driven by the Oersted field and spincurrent from theelectric current in the adjacentTa layer.

Source: Applied Physics Letters - November 4, 2016 Category: Physics Authors: Wenwen Kong, Xiaolong Fan, Hengan Zhou, Jiangwei Cao, Dangwei Guo, Y. S. Gui, C.-M. Hu and Desheng Xue Source Type: research