Figure 5: Extraction of the SOT coefficient from polar MOKE.
From: Quantifying interface and bulk contributions to spin–orbit torque in magnetic bilayers
The extraction is for the data shown in Fig. 1e. (a) Measured offset of line scan ΔV=V[+H,x]+V[−H,x] and the corresponding fitting curve based on equation (8). (b) By plotting the fitting curve and the measured data together, the parameters in equation (8) can be calibrated from linear fitting. In this example curve, the parameter is given as ηIc/w=45.5±1.2 μV. (c) Measured SOT signal of line scan ΔV=V[+H,x]−V[−H,x] and the corresponding fitting curve based on equation (9). (d) Linear extrapolation gives the parameter of SOT as ηhSOT=166±3 μV. Therefore, the SOT coefficient is determined as 
=1.83±0.7 nm.
