Elastic properties of a La$_{0.5}$Pr$_{0.2}$Ca$_{0.3}$MnO$_{3}$ single crystal

The temperature dependences of the velocity of longitudinal sound and internal friction in the ferromagnetic La$_{0.5}$Pr$_{0.2}$Ca$_{0.3}$MnO$_{3}$ single crystal with magnetic first-order phase transition were studied. It was found that the sound velocity decreases by $\approx$ 20% in transition from the ferromagnetic to paramagnetic state. In the paramagnetic region, the extended temperature hysteresis of the sound velocity and the internal friction was observed. It was shown that La$_{0.5}$Pr$_{0.2}$Ca$_{0.3}$MnO$_{3}$ has two paramagnetic phases with different sound velocities.