Related Experiment Video
Updated: Jun 4, 2025
08:00
Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
11.0K
Absence of High-Pressure Ground-State Reentrant Ferroelectricity in PbTiO_{3}.
R E Cohen1, Yangzheng Lin1, Muhtar Ahart2
1Extreme Materials Initiative, Earth and Planets Laboratory, <a href="https://ror.org/04jr01610">Carnegie Institution for Science</a>, Washington, DC 20015, USA.
Physical Review Letters
|December 23, 2024
Summary
Ferroelectricity in lead titanate disappears at moderate pressures due to zone boundary instabilities, not displacement squeezing. A new dense post-perovskite phase emerges at high pressures.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Geophysics
Background:
- Lead titanate (PbTiO3) is a classic perovskite ferroelectric material.
- Understanding its behavior under high pressure is crucial for materials science and geophysics.
- Previous studies suggested ferroelectricity is lost due to displacement squeezing.
Purpose of the Study:
- To investigate ferroelectricity in PbTiO3 under high pressure.
- To elucidate the mechanisms behind ferroelectric phase transitions.
- To identify new high-pressure phases of PbTiO3.
Main Methods:
- Density Functional Theory (DFT) computations.
- Experimental diamond-anvil techniques.
- Second harmonic generation spectroscopy.
Main Results:
- Ferroelectricity in PbTiO3 disappears at moderate pressures.
- DFT reveals zone boundary instabilities cause ferroelectric loss, contradicting prior theories.
- A new, dense, centrosymmetric post-perovskite phase (P21/m) becomes stable around 70 GPa.
Conclusions:
- The mechanism of ferroelectric loss in PbTiO3 under pressure is re-evaluated.
- High-pressure conditions stabilize a novel post-perovskite phase.
- This study offers new insights into the phase diagram of PbTiO3.
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