Thermally activated magnetization reversal in magnetic tunnel junctions  

作　　者：周广宏 王寅岗 祁先进 李子全 陈建康 

机构地区：[1]School of Materials Science and TechnoloJingy, Nanjing University of Aeronautics and Astronautics [2]Department of Mechanical Engineering, Huaiyin Institute of Technology

出　　处：《Chinese Physics B》2009年第2期790-794,共5页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No 50671048)

摘　　要：In this paper, the magnetization reversal of the ferromagnetic layers in the IrMn/CoFe/AlOx/CoFe magnetic tunnel junction has been investigated using bulk magnetometry. The films exhibit very complex magnetization processes and reversal mechanism. Thermal activation phenomena such as the training effect, the asymmetry of reversal, the loop broadening and the decrease of exchange field while holding the film at negative saturation have been observed on the hysteresis loops of the pinned ferromagnetic layer while not on those of the free ferromagnetic layer. The thermal activation phenomena observed can be explained by the model of two energy barrier distributions with different time constants.In this paper, the magnetization reversal of the ferromagnetic layers in the IrMn/CoFe/AlOx/CoFe magnetic tunnel junction has been investigated using bulk magnetometry. The films exhibit very complex magnetization processes and reversal mechanism. Thermal activation phenomena such as the training effect, the asymmetry of reversal, the loop broadening and the decrease of exchange field while holding the film at negative saturation have been observed on the hysteresis loops of the pinned ferromagnetic layer while not on those of the free ferromagnetic layer. The thermal activation phenomena observed can be explained by the model of two energy barrier distributions with different time constants.

关 键 词：magnetic tunnel junctions magnetization reversal thermal activation exchange cou~ pling 

分 类 号：O482.5[理学—固体物理]