Phenomenological approaches on the Nd3+ doped ferroelectric LaBGeO5

Date

2021-02-01

Author

Kara, N.
Kiraci, A.
Yurtseven, Hasan Hamit

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Two phenomenological models, namely the compressible Ising model and Landau model, have been used to analyze the specific heat and the dielectric constant data, respectively for the pure and Nd3+ doped LaBGeO5 (LBG) crystals. The critical exponent of the specific heat was extracted in both ferroelectric and paraelectric phases of the crystals studied here within the temperature intervals of [T - T-C vertical bar < 4 K. The extracted values of the critical exponent were then used to predict some thermodynamic quantities such as the enthalpy, entropy, and the Gibbs free energy. Regarding the analysis of dielectric constant data within the framework of the Landau theory, the observed values of the birefringence were associated with the order parameter below the transition temperature T-c. The Landau coefficients a(0) and a(4) were determined. Our results indicate a second-order phase transition mechanism.

URI

https://hdl.handle.net/11511/90033

Journal

FERROELECTRICS

DOI

https://doi.org/10.1080/00150193.2020.1868869

Collections

Department of Physics, Article

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Citation Formats

N. Kara, A. Kiraci, and H. H. Yurtseven, “Phenomenological approaches on the Nd3+ doped ferroelectric LaBGeO5,” FERROELECTRICS, pp. 13–26, 2021, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/90033.