| Project/Area Number |
17K14075
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Nanostructural physics
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
Sato Yohei 東北大学, 多元物質科学研究所, 准教授 (70455856)
|
|---|
| Project Period (FY) |
2017-04-01 – 2020-03-31
|
| Project Status |
Completed (Fiscal Year 2019)
|
| Budget Amount *help |
¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
Fiscal Year 2019: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2017: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
|
|---|
| Keywords | 電子エネルギー損失分光法 / 熱線遮蔽材料 / 運動量移送分解 / 運動量移送分解EELS / 物性実験 / 電子線分光 / 電子顕微鏡 |
|---|
| Outline of Final Research Achievements |
Cs-doped hexagonal WO3 (CWO) is used as a solar heat-shielding material for windows, in which plasma oscillation due to carrier electrons (carrier plasmon) plays an important role for near infrared scattering. Despite the hexagonal crystal structure of CWO, the anisotropic properties of the carrier plasmons have not been investigated. This study reports the momentum transfer resolved electron energy-loss spectroscopic measurements of CWO to investigate the anisotropic properties of carrier plasmons.
The experimental results clarified that the two plasma oscillation modes at 1.2 and 1.8 eV have different excitation properties in CWO. One plasma oscillation at 1.2 eV was oscillation mode along the ab plane with a large damping effect. Another mode at 1.8 eV was an oscillation along the c-axis with a small damping effect. These anisotropic plasmon modes led to an accurate understanding of the heat-shielding mechanism.
|
| Academic Significance and Societal Importance of the Research Achievements |
本研究成果により、電子顕微鏡を用いた運動量移送分解電子エネルギー損失分光法（q-EELS）の解析法を構築した。この手法を用いて、実用材料である熱線遮蔽物質Cs0.33WO3のプラズモン振動の異方性を明らかにした。近赤外領域で励起される2つのプラズモン振動モードが、広いエネルギー範囲の近赤外光を吸収する起源であることが明らかになり、高効率光吸収機構の解明に成功した。本解析手法による光散乱メカニズムの解明は、さらなる高効率フィルター材料を開発するための指針となり、新しい光機能性を持つマテリアルデザインへ役立つと期待される。
|
