Phenomenological approaches on the phase transition mechanisms of some ferroelectric materials

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2023-1-25

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Kara, Nazan

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Several phenomenological studies were carried out to investigate the phase transition mechanisms of some ferroelectric crystals. In particular, we focused on the compressible Ising model to explain the anomalous behavior of specific heat for such ferroelectrics exhibiting second-order phase transitions in the vicinity of the transition temperatures. The temperature dependence of some thermodynamic functions such as internal energy, enthalpy, entropy, and free energy of some ferroelectric materials was also predicted. The thermodynamic quantities of ferroelectrics are obtained by calculating the order parameters using the experimental data from the literature. The calculated results are then interpreted with the ones stated in previous experimental studies.

Subject Keywords

Phase Transition, Ferroelectrics, Ising Model, Landau Theory

URI

https://hdl.handle.net/11511/102769

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

N. Kara, “Phenomenological approaches on the phase transition mechanisms of some ferroelectric materials,” Ph.D. - Doctoral Program, Middle East Technical University, 2023.