Abstract
The dependence of polarization on the temperature in ferroelectric bulk is investigated. In order to correctly predict the phase transition phenomena, we suggest to pass from the Landau-Ginzburg-Devonshire model to the Landau-Khalatnikov equation with simultaneous consideration of the pyroelectric effect. The developed approach allows us to derive an analytical expression describing the polarization behavior in the vicinity of the Curie point. Additionally, the analysis of obtained equations explains the temperature hysteresis with the difference of physical values at heating and cooling cycles. The model is verified by comparison between experimental data and theoretical results.
Acknowledgments
The authors would like to thank Dr. A.I. Dedyk from the Saint-Petersburg State Electrotechnical University for presented experimental data. The work was performed with support of the “Development of Scientific Potential of Higher Education 2009–2011” state program of the Ministry of Education and Science of the Russian Federation, project no2.1.2/5063.