EFFECT OF REGIMES OF COOLING IN A MAGNETIC-FIELD ON THE MAGNETIZATIONOF A LA0.9SR0.1MNO3 SINGLE-CRYSTAL

Magnetization measurements were performed on a lanthanum manganite La0 .9Sr0.1MnO3 single crystal in the temperature interval 4.2-300 K and m agnetic field interval 50 Oe-55 kOe in two sample cooling regimes: 1) cooling down to 4.2 K in a high (55 kOe) magnetic field, and 2) coolin g in a ''zero'' field. It is shown that the temperature dependences of the magnetization M(T) are substantially different in these regimes. Pronounced anomalies of M(T) were observed at temperatures T = 103 K and T-c = 145 K. The first anomaly is attributed to a structural trans ition, while the second one corresponds to a ferromagnet-paramagnet ph ase transition. The magnetization of a La0.9Sr0.1MnO3 single crystal i n the cooling regimes studied shows typical ''spin-glass'' behavior. ( C) 1998 American Institute of Physics.