Figure 5: STT on the CoFeB layer.

(a) Kerr rotation of the CoFeB-2 nm sample with pump fluence of 17 J m⁻² with the [Co/Pt] magnetization up (black square) or down (red circle). (b) The normalized precession amplitude, ΔM/M, of the CoFeB with different pump fluence up to 17 J m⁻² (black circle). The dotted line is the linear fitting of data. (c) The calculated spin current that goes to CoFeB in the CoFeB-2 nm sample. The calculation is done by the spin diffusion simulation. (d) The precession data and magnetization dynamics simulation. The precession data (black circle) is obtained by subtracting the demagnetization signal of a at the [Co/Pt] magnetization up. The magnetization dynamics simulation (black solid line) is done by Landau–Lifshitz–Gilbert equation with an input spin current of c.