Fig. 2

Hysteresis parameters displayed in a a Day plot, and b a function of coercivity and remanence ratio. SD: single domain, PSD: pseudo-single domain, MD: multi-domain. The colors correspond to the samples shown in Fig. 3: red indicates sample A1 (Fig. 3a); orange indicates sample B4 (Fig. 3b), magenta indicates sample B8 (Fig. 3c), green indicates sample C7 (Fig. 3d), blue indicates sample A11 (Fig. 3e), and purple indicates sample C2 (Fig. 3f)