Anomalous temperature dependence of the magnetization in La0.84Sr0.16MnO3

作者：Marysko M^*; Savosta M M; Jirak Z; Novak P

来源：Journal of Applied Physics, 2009, 105(7): 07D716.

DOI：10.1063/1.3072079

The superconducting quantum interference device (SQUID) magnetization measurements have been performed on single crystal manganites La1-xSrxMnO3 (x=0.16;0.17) previously studied by the NMR method. For the x=0.16 sample an anomaly in the temperature dependence of the saturation magnetization at T-1 approximate to 130 K is observed, which manifests itself as a cusp in dm/dT. This temperature lying well below the metal-insulator transition at T-MI=157 K seems to correspond to an orbital ordering temperature T-oo indicated also by the decrease in the low field FC susceptibility. The observed anomaly, which is also reproduced in the temperature dependence of the NMR frequency, is ascribed to a continual decrease in the exchange interaction within the temperature interval 60 K and the difference between T-MI and T-oo to an inherent inhomogeneity in Sr concentration. The relative SQUID magnetizations are compared with the NMR values.

• 出版日期2009-4-1