Упругие свойства монокристаллов La-=SUB=-0.7-y-=/SUB=-Pr-=SUB=-y-=/SUB=-Ca-=SUB=-0.3-=/SUB=-MnO-=SUB=-3-=/SUB=- (0≤ y≤0.3)

Abstract

Results of the investigation of the temperature dependences of the velocity of longitudinal sound and internal friction in the ferromagnetic La 0.7-y Pr y Ca 0.3 MnO3 single crystals (0≤ y≤0.3) with first-order magnetic phase transition are presented. In the paramagnetic state, the temperature dependences of the velocity of sound and the internal friction demonstrate extended temperature hysteresis, which indicates the ingomogeneity of the paramagnetic state. It seems likely that the main reason of this ingomogeneity is structural phase separation.