Related Experiment Video
Updated: Jun 11, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
8.7K
Domain Dynamics Response to Polarization Switching in Relaxor Ferroelectrics
Yang Li1, Wei Lin1, Cong Wang2
1Inner Mongolia Key Laboratory of Nanoscience and Nanotechnology & Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, China.
Advanced Materials (Deerfield Beach, Fla.)
|October 10, 2024
Summary
Researchers visualized nanoscale polar regions (nanodomains) during polarization switching in relaxors. Two distinct switching pathways were revealed, linking micro-domain dynamics to macro-polarization behavior for material design.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Nanoscale polar regions (nanodomains) are key to relaxor ferroelectric properties.
- Understanding nanodomain evolution during polarization switching is experimentally challenging.
- Linking microscopic domain dynamics to macroscopic properties requires advanced characterization.
Purpose of the Study:
- To visualize and understand the real-time evolution of nanodomains during polarization switching.
- To reveal the distinct pathways and dynamics of nanodomain switching.
- To bridge the gap between micro-domain dynamics and macro-polarization switching in relaxors.
Main Methods:
- In situ experimental observation and visualization of nanodomains.
- Utilizing Bi5-xLaxMg0.5Ti3.5O15 as an exemplary relaxor system.
- Analysis of polarization switching pathways and Landau energy landscapes.
Main Results:
- Two distinct polarization switching pathways were identified: steep bipolar-like and flat multi-step.
- A stable non-polar mesophase was observed mediating polarization states in multi-step switching.
- Switching pathways are dictated by Landau energy landscapes, domain configurations, and interdomain interactions.
Conclusions:
- This study provides direct visualization of nanodomain dynamics during polarization switching.
- The findings reveal two fundamental switching mechanisms in relaxor ferroelectrics.
- The results offer a guiding principle for designing and optimizing relaxor materials.
More Related Videos
Related Concept Videos
01:31Dielectric Polarization in a Capacitor
4.6K
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
4.6K
01:28Induced Electric Dipoles
4.2K
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
4.2K
01:23Atomic Nuclei: Nuclear Relaxation Processes
632
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
632
01:29Potential Due to a Polarized Object
369
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
369
01:31Ferromagnetism
2.4K
Materials like iron, nickel, and cobalt consist of magnetic domains, within which the magnetic dipoles are arranged parallel to each other. The magnetic dipoles are rigidly aligned in the same direction within a domain by quantum mechanical coupling among the atoms. This coupling is so strong that even thermal agitation at room temperature cannot break it. The result is that each domain has a net dipole moment. However, some materials have weaker coupling, and are ferromagnetic at lower...
2.4K
01:27Electrostatic Boundary Conditions in Dielectrics
1.1K
When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's...
1.1K