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Updated: Jun 25, 2026
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
Polarization and adiabatic pumping in inhomogeneous crystals
Di Xiao1, Junren Shi, Dennis P Clougherty
1Department of Physics, The University of Texas at Austin, Austin, Texas 78712, USA. xiaod@ornl.gov
Physical Review Letters
|March 5, 2009
Summary
We present a new theory for electric polarization in crystals with varying order. This theory separates polarization into perturbative and topological parts, linking microscopic details to macroscopic properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Theoretical Physics
Background:
- Electric polarization in crystalline solids is a fundamental property.
- Understanding polarization in systems with inhomogeneous order is crucial for advanced materials.
- Existing theories often struggle to fully capture the complexities of inhomogeneous systems.
Purpose of the Study:
- To develop a general theoretical framework for electric polarization in crystals with inhomogeneous order.
- To classify the contributions to inhomogeneity-induced polarization.
- To establish a comprehensive link between microscopic models and macroscopic polarization.
Main Methods:
- Development of a general theory for electric polarization.
- Classification of polarization into perturbative and topological contributions.
- Utilizing the Chern-Simons form of Berry gauge fields for topological analysis.
Main Results:
- Electric polarization in inhomogeneous crystals can be divided into a perturbative correction and a topological contribution.
- The topological contribution is quantized and related to the second Chern number.
- The theory establishes an exhaustive connection between microscopic crystal structures and macroscopic polarization.
Conclusions:
- The developed theory provides a unified approach to understanding electric polarization in inhomogeneous crystalline materials.
- The distinction between perturbative and topological polarization offers new insights into material properties.
- This work bridges the gap between fundamental theory and practical material design.
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