纳米尺寸自旋阀中电流驱动的自旋波发射  

Spin Wave Emitting Effect Driven by Current-Induced Spin Transfer Torque in PSV

作　　者：胡九宁[1,2,3] 陈培毅[1,2,3] 张磊[1,2,3] 任敏[1,2,3] 董浩[1,2,3] 邓宁[1,2,3] 

机构地区：[1]清华大学微电子学研究所,北京100084 [2]清华大学清华信息科学与技术国家实验室(筹),北京100084 [3]清华大学微纳电子系,北京100084

出　　处：《微纳电子技术》2008年第10期568-572,共5页Micronanoelectronic Technology

基　　金：高等学校博士学科点专项科研基金资助项目(20060003067);973重大科学研究计划资助项目(2006CB921106);自然科学基金资助项目(60606021)

摘　　要：提出了在纳米赝自旋阀中的电流感应自旋传输矩的磁动力学描述,成功地解释了在磁纳米多层结构中的电流驱动微波发射和电流感应磁化翻转现象。自旋流极化由在电导匹配时的自旋流和化学势连续性边界条件决定。自旋矩的纵向和横向分量在自旋阀的电流驱动微波发射和电流感应磁化翻转现象中扮演了不同的角色:纵向自旋矩分量决定了电流感应磁化翻转(CIMS)效应,而横向自旋矩是自旋波发射(SWE)效应所不可缺少的。根据这一理论,由LLG方程自然得到自旋波发射的双模,分别为横向自旋矩引发的X和Y方向的振动,并引起磁多层电阻以频率2w或w(进动频率)随时间变化。磁场和自旋流共同决定了自旋波发射的频率和功率,这一理论预言了某种特殊的磁多层结构,如磁层相互垂直的结构,将具有大得多的微波发射效率,这一结论已经被实验所证实。A magnetic dynamics description for current-induced spin transfer torque （STT） in pseudo-spin-valve （PSV） was presented, and the effects of SWE and CIMS in magnetic multiplayer nanostructures were illuminated. The spin current polarization is determined by the continuity boundary condition of spin current and chemical potential under the case of conduction matching. The roles of longitudinal and transverse components of STT are different in magnetic multiplayer that longitudinal one generates current induced magnetic switching （CIMS） effect, while transverse one is necessary for spin wave emitting （SWE） effect. From the theory, the double spin wave modes have been naturally are X mode and Y mode, respecti magnetic multiplayer altering following obtained by Landau-Lifshitz-Bilbert （LLG） equation, which vely, due to the transverse STT, and cause resistance of time with frequency 2 w or w （precession frequency）. Magnetic field and spin current control frequency and power of SWE according to this theory, which predicts a special device structure, for example, the perpendicular configuration, should present much higher efficiency of SWE that has been demonstrated by some experiment results.

关 键 词：自旋波发射 自旋传输矩 Landau-Lifshitz-Gilbert方程 自旋振荡模式 磁多层 

分 类 号：TB383[一般工业技术—材料科学与工程] O482.5[理学—固体物理]