On the temperature dependence of coercivity and exchange biasing field in La–Ca–Mn–O ferromagnetic/antiferromagnetic multilayers

Abstract Two series of exchange-coupled [La1−xCaxMnO3(4 nm)/La1−yCayMnO3 (4 nm)]15 multilayers (one with constant y=0.67 while x=0.33, 0.4, 0.48, and the other with constant x=0.4 while y=0.52, 0.75) were used to investigate the effect of the field cooling on both, the exchange-biasing field (HEB) and the coercivity (Hc). Large magnetothermal irreversibilities result in spin-glass-like M(T) curves. Exchange bias appears below a blocking temperature TB≈70 K. Between 5 and 70 K, the M(H) loops exhibit an asymmetry between the magnetization reversal from +M to −M and that from −M to +M, which seems to depend strongly on the domain structure in the FM layers.