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Order-disorder transition in the ferroelectric LiTaO3
Date
2019-10-26
Author
KİRACI, ALİ
Yurtseven, Hasan Hamit
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The temperature dependences of the damping constant and the relaxation time are calculated by using the Raman frequencies of a* and the lowest A(1) (TO) phonons in the ferroelectric phase close to the ferroelectric-paraelectric transition in LiTaO3 (T-C = 963 K). Both calculations are performed by considering the frequency as an order parameter for the pseudospin-phonon (PS) and the energy fluctuation (EF) models using the observed data from the literature. Values of the activation energies of this crystal are also deduced by using both models in this crystal. Our results show that the PS and EF models can describe the observed behavior adequately for the order-disorder transition in LiTaO3.
Subject Keywords
Electronic, Optical and Magnetic Materials
,
Condensed Matter Physics
URI
https://hdl.handle.net/11511/37680
Journal
FERROELECTRICS
DOI
https://doi.org/10.1080/00150193.2019.1671068
Collections
Department of Physics, Article
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A. KİRACI and H. H. Yurtseven, “Order-disorder transition in the ferroelectric LiTaO3,”
FERROELECTRICS
, pp. 235–244, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37680.