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Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
Tetragonal tungsten bronze compounds: relaxor versus mixed ferroelectric-dipole glass behavior
1Institute of Physics, Opole University, Opole, 45-052, Poland. stef@math.uni.opole.pl
Summary
This study explains experimental data on a tungsten bronze compound, showing it transitions from ferroelectric to orientational glass behavior, not relaxor. This ferroelectric-to-glass crossover is modeled using the disordered Ising model.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Crystallography
Background:
- Tungsten bronze compounds (TBCs) exhibit complex dielectric properties.
- Distinguishing between ferroelectric, relaxor, and glass behaviors is crucial for materials applications.
- Recent experiments on Ba(2)Pr(x)Nd(1-x)FeNb(4)O(15) present new data on TBCs.
Purpose of the Study:
- To theoretically explain recent experimental findings on the Ba(2)Pr(x)Nd(1-x)FeNb(4)O(15) compound.
- To model the observed crossover in dielectric behavior.
- To differentiate between ferroelectric, orientational glass, and relaxor states in TBCs.
Main Methods:
- Utilizing a theoretical model based on the disordered Ising model.
- Applying the replica-symmetric solution for theoretical analysis.
- Comparing model predictions with experimental data from Castel et al. (2009).
Main Results:
- The proposed model successfully explains the experimental data for Ba(2)Pr(x)Nd(1-x)FeNb(4)O(15).
- A crossover from ferroelectric (at x=0) to orientational (dipole) glass (at x=1) behavior is predicted and supported.
- The presence of ferroelectric hysteresis loops confirms the transition, distinguishing it from typical relaxor behavior.
Conclusions:
- The compound Ba(2)Pr(x)Nd(1-x)FeNb(4)O(15) exhibits a ferroelectric to orientational glass phase transition.
- The disordered Ising model provides a valid framework for understanding this crossover.
- This work clarifies the nature of phase transitions in TBCs, differentiating them from perovskite relaxors.
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