Dependence of switching process on the perpendicular magnetic anisotropy constant in P-MTJ  

作　　者：Mao-Sen Yang Liang Fang Ya-Qing Chi 杨茂森;方粮;池雅庆(State Key Laboratory of High-Performance Computing, College of Computer, National University of Defense Technology;Institute of Microelectronics, College of Computer, National University of Defense Technology)

机构地区：[1]State Key Laboratory of High-Performance Computing,College of Computer,National University of Defense Technology,Changsha 410073,China [2]institute of Microelectronics,College of Computer,National University of Defense Technology,Changsha 410073,China

出　　处：《Chinese Physics B》2018年第9期635-638,共4页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.61332003);the Natural Science Foundation of Hunan Province,China(Grant No.2015JJ3024)

摘　　要：We investigate the dependence of the switching process on the perpendicular magnetic anisotropy （PMA） constant in perpendicular spin transfer torque magnetic tunnel junctions （P-MTJs） using micromagnetic simulations. It is found that the final stable states of the magnetization distribution of the free layer after switching can be divided into three different states based on different PMA constants： vortex, uniform, and steady. Different magnetic states can be attributed to a trade-off among demagnetization, exchange, and PMA energies. The generation of the vortex state is also related to the non-uniform stray field from the polarizer, and the final stable magnetization is sensitive to the PMA constant. The vortex and uniform states have different switching processes, and the switching time of the vortex state is longer than that of the uniform state due to hindrance by the vortex.We investigate the dependence of the switching process on the perpendicular magnetic anisotropy （PMA） constant in perpendicular spin transfer torque magnetic tunnel junctions （P-MTJs） using micromagnetic simulations. It is found that the final stable states of the magnetization distribution of the free layer after switching can be divided into three different states based on different PMA constants： vortex, uniform, and steady. Different magnetic states can be attributed to a trade-off among demagnetization, exchange, and PMA energies. The generation of the vortex state is also related to the non-uniform stray field from the polarizer, and the final stable magnetization is sensitive to the PMA constant. The vortex and uniform states have different switching processes, and the switching time of the vortex state is longer than that of the uniform state due to hindrance by the vortex.

关 键 词：magnetic tunnel junction perpendicular magnetic anisotropy vortex state micromagnetic simula-tion 

分 类 号：O469[理学—凝聚态物理]