(color online) OOP demagnetization curves of Nd–Dy–Fe–Co–B (100 nm)/S/Fe (10 nm). (a) The thicknesses of the Ta spacer layers are 2 nm, 20 nm, 100 nm, 150 nm and (b) the thicknesses of the Cr₂O₃ spacer layers are 2 nm, 10 nm, 15 nm, 20 nm.^[31]