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Phenomenological Description of a Giant Temperature Hysteresis of the Ultrasound Velocity and the Internal Friction in Lanthanum Manganite

A. P. Saiko·S. A. Markevich
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Abstract

We propose an explanation for the experimentally observed [JETP Lett. 74, 115 (2001)] 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.

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A. P. Saiko, S. A. Markevich. 2003-09-29. Phenomenological Description of a Giant Temperature Hysteresis of the Ultrasound Velocity and the Internal Friction in Lanthanum Manganite. https://doi.org/10.1134/1.1625736

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