Saiko A.P. and Markevich S.A.
We propose
an explanation for the experimentally observed giant temperature hysteresis of
the ultrasound velocity and the internal friction in single crystals of
lanthanum manganite (La0.8Sr0.2MnO3). The effect is interpreted within the
framework of a phenomenological model based on the notion of two coexisting
sublattices of the oxygen octahedra performing cooperative tilting-rotational
oscillations in bistable potential fields.