Polarization mechanism in hybrid perovskite-type ferroelectric crystals
Abstract
Two types of conventional ferroelectrics, (a) displacive-type and (b) order-disorder-type ferroelectrics, have been known to exist.Recently, perovskite-type ferroelectric crystals were prepared by using polar molecules with large anisotropy1), and the mechanism of ferroelectricity in these crystals was investigated, and it was found that they are new ferroelectrics in which two types of ferroelectricity, displacive-type and order-disorder-type, coexist in the one unit cell. Recent studies of this material have shown the possibility of creating hybrid-type ferroelectrics without metal or halide ions by satisfying the following three conditions: (1) use of polar molecular ions with large anisotropy, (2) satisfaction of perovskite-type structure tolerance factors, and (3) satisfaction of electrical neutrality conditions. In such hybrid-type ferroelectrics, the mechanism of piezoelectricity is mainly the rotationof polar molecules with large anisotropy to the direction of the applied electric field, while the mechanism of dielectricity is the displacement of other polar molecules to the direction of the applied electric field. As a result, since piezoelectricity and dielectricity can be independently controlled, the creation of materials with unique piezoelectric and dielectric properties, that have never been seen before, can be expected.1) Heng-Yun Ye et. al., Science, 361, 151-155 (2018).
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 10, 2025
- Source ID
- N629092512022
Entities
People
- Satoshi Wada
Organizations
- Office of Naval Research
- United States Navy
- University of Yamanashi