| Project/Area Number |
16K17732
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Condensed matter physics II
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
AOYAMA Takuya 東北大学, 理学研究科, 助教 (80757261)
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Project Status |
Completed (Fiscal Year 2018)
|
| Budget Amount *help |
¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000)
Fiscal Year 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2016: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
|
|---|
| Keywords | 強相関電子物性 / 遷移金属化合物 / マルチフェロイクス / フラストレーション / 磁気多極子 / 5d電子系 / フラストレート磁性体 / 誘電率 / 高圧力 / 磁性 / 誘電性 / 強相関電子系 |
|---|
| Outline of Final Research Achievements |
We measured the magnetoelectric effect of a compound containing trivalent ruthenium whose electronic configuration is same as tetravalent iridium. We observed the magnetodielectric effect due to the broken local space inversion symmetry. Infrared absorption spectra were measured to reveal details.
Single crystals of frustrated magnetic material containing tetravalent iridium cation were grown, X-ray crystal structure analysis, magnetoresistance effect, and specific heat were measured, and it was revealed that semimetal-like conduction characteristics are exhibited and magnetic transition occurs at low temperature. Moreover, we performed the resistivity measurement under pressure, and the pressure dependence of the magnetic transition was measured.
|
| Academic Significance and Societal Importance of the Research Achievements |
ハニカム格子上においてボンド依存した強磁性相互作用をもつ場合，その基底状態は量子スピン液体になることが厳密に示されている．また遍歴および局在した分数励起によって有限温度の振る舞いが記述でき，そのうち遍歴自由度がDirac型の分散を示すことからトポロジカルな性質を持つことが指摘されている．我々は磁気誘電測定および赤外吸収スペクトル測定を通じて遍歴自由度の観測を試みた．その結果磁気転移温度以下で顕著な磁気誘電効果を観測するとともに，複数のフォノンに関連した新たな吸収を発見した．
|
