Related Experiment Video
Updated: Jul 30, 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
11.1K
Hybrid Improper Ferroelectricity in Columnar (NaY)MnMnTi4 O12
Rebecca Scatena1,2, Ran Liu3,4, Vladimir V Shvartsman5
1Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK.
Angewandte Chemie (International Ed. in English)
|May 18, 2023
Summary
We discovered hybrid improper ferroelectricity in columnar perovskites through cation ordering, leading to a polar phase. This ordering also induces ferroelectric order and coexisting electric and magnetic dipoles below 12 K.
Area of Science:
- Solid-state chemistry
- Materials science
- Crystallography
Background:
- Perovskites are a versatile class of materials with tunable properties.
- Hybrid improper ferroelectricity is a phenomenon observed in certain perovskite structures.
- Understanding cation ordering is crucial for controlling material properties.
Purpose of the Study:
- To investigate the emergence of ferroelectricity in columnar perovskites.
- To explore the relationship between cation ordering and structural distortions.
- To examine the coexistence of electric and magnetic ordering.
Main Methods:
- Synthesis and characterization of the columnar perovskite (NaY)MnMnTi4O12.
- Analysis of crystal structure and cation ordering via annealing temperature.
- Investigation of ferroelectric and magnetic properties through temperature-dependent measurements.
Main Results:
- Cation ordering coupled with octahedral tilts induces a polar phase in (NaY)MnMnTi4O12.
- This mechanism represents hybrid improper ferroelectricity in columnar perovskites.
- Annealing temperature controls cation ordering, which polarizes Mn2+ dipoles and establishes ferroelectric order.
- Coexistence of ordered electric and magnetic dipoles on the same sublattice below TN ≈12 K.
Conclusions:
- Columnar perovskites can exhibit hybrid improper ferroelectricity.
- Cation ordering is a key mechanism for achieving ferroelectric states in these materials.
- (NaY)MnMnTi4O12 is a rare system showcasing coupled electric and magnetic ordering.
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