Figure 3: Quantification of the SOT and SOF coefficients.
From: Quantifying interface and bulk contributions to spin–orbit torque in magnetic bilayers
(a). Measured SOT coefficient of Ti(1)/CoFeB(x)/Pt(5), where x spans from nominal 0.65 to 5.75 nm. The inset shows the 1/dCoFeB dependence of the SOT coefficients. Here the error bar of the y axis is obtained from the linear regression, as discussed in the Methods section. The error bar of the x axis is because of possible misalignment in fabricating the wedge-shaped sample, as described in the Methods section. (b) Measured SOF coefficient of the same series of samples as in a. The SOF remains nearly zero when the CoFeB is thick and increases rapidly as the CoFeB becomes thinner than 1 nm. The inset shows the SOT and SOF of Ti(1)/CoFeB(x)/Cu(2)/Pt(5), where the direct interface between CoFeB and Pt is removed.
