Manipulating magnetic anisotropy and ultrafast spin dynamics of magnetic nanostructures*
Cheng Zhao-Hua†, He Wei, Zhang Xiang-Qun, Sun Da-Li, Du Hai-Feng, Wu Qiong, Ye Jun, Fang Ya-Peng, Liu Hao-Liang
       
(a) Power spectral density of Fe/MgO(001) film obtained by fast Fourier transform of the TR-MOKE data with the pump laser fluences at 2.5 mJ/cm2, 7.1 mJ/cm2, 16.5 mJ/cm2, and 19.1 mJ/cm2. (b) Values of the peak in the spectra as a function of the laser fluence. The f 1 and f 2 denote the frequencies of the first and the second peaks in panel (a).[ 91 ]