Microscopic inhomogeneities in a La$_{1-x}$Sr$_x$MnO$_3$ ($\mathbf{x=0.175}$) manganite crystal and generation of coherent magnetoelastic oscillations on these inhomogeneities

The temperature dependences of the amplitude and velocity of ultrasonic waves at a frequency of 770 MHz were measured in a La$_{1-x}$Sr$_x$MnO$_3$ ($x=0.175$) manganite single crystal. Magnetoelastic wave generation was observed near the magnetic phase transition. The temperature dependences of the magnetization and magnetostriction correlated with the temperature behavior of the amplitude and velocity of the magnetoelastic wave, which suggests that the coherent magnetoelastic oscillations were generated on microscopic inhomogeneities (magnetoelastic domains) typical for a manganite of the given composition.