Thermal-magnetic noise measurement of spin-torque effects on ferromagnetic resonance in MgO-based magnetic tunnel junctions
Thermal-magnetic noise measurement of spin-torque effects on ferromagnetic resonance in MgO-based magnetic tunnel junctions
复制标题
氧化镁基磁隧道结中自旋扭矩对铁磁共振影响的热磁噪声测量
DOI：
10.1063/1.3212870
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发表时间：
2009
影响因子：
4
通讯作者：
S. Parkin
中科院分区：
文献类型：
--
作者：
Y. Guan;Jonathan Z. Sun;Xin Jiang;R. Moriya;Li Gao;S. Parkin
铁磁共振热磁噪声（T-FMR）可以用来测量纳米磁性隧道结（MTJ）的磁垂直各向异性。为了这个目的，T-FMR测量进行与外部磁场高达14千奥斯特垂直施加到膜表面的MgO基MTJ下的直流偏置。观察到的频率-场关系表明，20 A CoFeB自由层具有比CoFeB的本征体值小得多的有效退磁场，4πMeff=6.1±0.3 kOe。 这个值是一致的饱和磁场从相同的CoFeB厚度的扩展膜上的磁力测量。另一方面，面内T-FMR对于有效退磁场显示出不太一致的结果，这可能是由于更复杂模式的激发。这些实验表明，垂直T-FMR是首选的纳米MTJ的定量磁表征。
Thermal-magnetic noise at ferromagnetic resonance (T-FMR) can be used to measure magnetic perpendicular anisotropy of nanoscale magnetic tunnel junctions (MTJs). For this purpose, T-FMR measurements were conducted with an external magnetic field up to 14 kOe applied perpendicular to the film surface of MgO-based MTJs under a dc bias. The observed frequency-field relationship suggests that a 20 A CoFeB free layer has an effective demagnetization field much smaller than the intrinsic bulk value of CoFeB, with 4πMeff=6.1±0.3 kOe. This value is consistent with the saturation field obtained from magnetometry measurements on extended films of the same CoFeB thickness. In-plane T-FMR on the other hand shows less consistent results for the effective demagnetization field, presumably due to excitations of more complex modes. These experiments suggest that the perpendicular T-FMR is preferred for quantitative magnetic characterization of nanoscale MTJs.
影响因子：
19.6
作者：
Deac, Alina M.;Fukushima, Akio;Watanabe, Naoki
通讯作者：
Watanabe, Naoki