Figure 2.

(a) Polar MOKE hysteresis loops of Pt/Co(t)/Pt with t = 0.85 nm (blue lines), 0.95 nm (green lines) and 1.0 nm (red lines). The solid lines represent the unstrained films and the dashed lines show the hysteresis loops under tensile out-of-plane strain induced by applying 150 V to the piezoelectric transducers. (b) The coercive fields of the hysteresis loops are plotted against Co thickness. The solid shapes are the unstrained films and the open shapes are the strained films. The error bars are smaller than the data points.