Related Experiment Video
Updated: Jan 16, 2026
06:44
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
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Tunable and Persistent Macroscopic Polarization in Nominally Centrosymmetric Defective Oxides.
Dae-Sung Park1,2,3, Nini Pryds1, Nicolas Gauquelin4
1Department of Energy Conversion and Storage, Technical University of Denmark, Fysikvej, Kongens Lyngby, 2800, Denmark.
Advanced Materials (Deerfield Beach, Fla.)
|September 26, 2025
Summary
Defects in Gadolinium Cerium Oxide (GdxCe1-xO2-δ) films create built-in polarization, enabling switchable pyroelectric effects. This defect-mediated symmetry breaking offers a path to new polar materials for energy applications.
Area of Science:
- Materials Science
- Solid State Physics
- Oxide Electronics
Background:
- Symmetry breaking in materials is crucial for emergent functionalities.
- External stimuli like electric fields can induce symmetry breaking and polarization.
- Defects and their clustering can lead to non-zero dipole moments and altered material properties.
Purpose of the Study:
- To demonstrate a conceptual approach for defects-mediated symmetry breaking in nominally centrosymmetric oxides.
- To achieve built-in polarization in Gadolinium Cerium Oxide (GdxCe1-xO2-δ) films via macroscopic charge asymmetry.
- To investigate the relationship between oxygen vacancy redistribution and polarization in these films.
Main Methods:
- Fabrication of GdxCe1-xO2-δ (CGO) films.
- Application of electric fields to induce charge asymmetry and study defect redistribution.
- Measurement of polarization and pyroelectric effect at room temperature.
Main Results:
- Achieved switchable and enduring polarization in CGO films.
- Identified electric field-driven redistribution of oxygen vacancies as the governing mechanism.
- Determined a critical field strength of approximately 0.5 MV cm-1 for polarization switching.
- Observed a persistent pyroelectric effect with a coefficient of approximately 180 µC m-2 K-1.
Conclusions:
- Defect-mediated symmetry breaking can induce polarization in centrosymmetric oxides.
- The electric field-driven redistribution of oxygen vacancies is a viable mechanism for creating switchable polarization.
- This approach offers potential for developing sustainable, high-performance polar film materials for energy and electronic applications.
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