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Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Ferroelectric phase transition in LiNbO3: Insights from molecular dynamics
Simone Sanna1, Wolf Gero Schmidt
1Lehrstuhl für Theoretische Physik, Universität Paderborn, Paderborn, Germany. simone.sanna@uni-paderborn.de
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
|September 26, 2012
Summary
This study models the ferroelectric-paraelectric phase transition in lithium niobate (LiNbO3) using ab initio molecular dynamics. The transition is a continuous process, not abrupt, with mixed displacive and order-disorder characteristics.
Area of Science:
- Condensed matter physics
- Materials science
- Computational chemistry
Background:
- Lithium niobate (LiNbO3) is a crucial material exhibiting ferroelectric properties.
- Understanding its phase transitions is vital for device applications.
- Previous models often simplified the transition dynamics.
Purpose of the Study:
- To model the ferroelectric-paraelectric phase transition in LiNbO3.
- To investigate the nature of the structural phase transition.
- To elucidate the combined displacive and order-disorder characteristics.
Main Methods:
- Utilizing ab initio molecular dynamics simulations.
- Employing density functional theory (DFT) for electronic structure calculations.
- Analyzing the behavior of ionic species during the phase transition.
Main Results:
- The ferroelectric-paraelectric phase transition in LiNbO3 is a continuous process over approximately 100K.
- Different ionic species (Li and Nb) exhibit distinct behaviors at varying temperatures.
- The transition displays a combination of displacive and order-disorder characteristics.
Conclusions:
- The phase transition in LiNbO3 is more complex than previously assumed.
- The interplay between Li and Nb sublattice dynamics dictates the transition mechanism.
- This detailed understanding can inform the design of advanced LiNbO3-based devices.
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