Elastic properties of La1−xBaxMnO3 single crystals

We report the temperature dependence of the longitudinal sound velocity and internal friction in La1−xBaxMnO3 single crystals, x = 0.15; 0.20; 0.25, over the temperature range of 6-420 K. The sound velocity in La-Ba manganites is found to be essentially smaller than in La-Sr manganites. In all the La-Ba crystals, a structural transition from the low-temperature orthorhombic phase to the high-temperature rhombohedral phase is observed. A giant thermal hysteresis of the longitudinal sound velocity and internal friction connected with the structural transition is found.