On the low-temperature anomaly in the AC susceptibility of La0.9Ca0.1MnO3

Abstract The substituted manganate La 0.9 Ca 0.1 MnO 3 undergoes a ferromagnetic transition at T c =157 K and a decrease in the AC susceptibility as well as zero-field-cooled (ZFC) magnetization measured using very low DC magnetic fields which is observed below ∼100 K. This low-temperature anomaly below ∼100 K is not observed in the field-cooled magnetization measured using the same small DC magnetic fields used for the ZFC measurements. Initial magnetization and magnetic hysteresis measurements show no difference in the M – H behavior above and below 100 K and indicate the multidomain ferromagnetic behavior of the compound. A small sharp increase in the coercivity of the material is observed below 100 K, corresponding to the drop in the AC susceptibility. The anomaly, at low temperatures, in the AC susceptibility and low-field ZFC magnetization of La 0.9 Ca 0.1 MnO 3 can be explained in terms of domain wall pinning effects.