| Budget Amount *help |
¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000)
Fiscal Year 2019: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000)
Fiscal Year 2018: ¥7,020,000 (Direct Cost: ¥5,400,000、Indirect Cost: ¥1,620,000)
Fiscal Year 2017: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
|
|---|
| Outline of Final Research Achievements |
Ferroelectric materials such as PMN-PT are known as relaxor ferroelectrics characterized by inhomogeneous nanostructures known as polar nano-regions. To elucidate ferroelectric domain switching mechanism, we employed in situ biasing in a high-voltage electron microscope (HVEM) equipped with a direct electron detection (DED) CMOS camera. We developed a novel electrical biasing specimen holder for in situ HVEM observation. The DED camera enables fast image acquisition with a frame rate of 400 fps. Microstructures of the PMN-0.3PT specimens were composed of ferroelectric domains, 100～200 nm in sizes, oriented [110] and [1-10] directions. By applying electric field (1 kV/mm) in the [110] directions, domain switching initiated at a corner of a domain, and propagated rapidly. Domain switching kinetics was analyzed based on the Kolmogolov-Avrami-Ishibashi model and found that the switching proceeds via two-dimensional nucleation and growth (n = 2.4-3.2).
|
