Project Area | Novel States of Matter Induced by Frustration |
Project/Area Number |
19052001
|
Research Category |
Grant-in-Aid for Scientific Research on Priority Areas
|
Allocation Type | Single-year Grants |
Review Section |
Science and Engineering
|
Research Institution | The University of Tokyo (2010-2011) Tohoku University (2007-2009) |
Principal Investigator |
ARIMA Taka-hisa (ARIMA Takahisa) 東京大学, 大学院・新領域創成科学研究科, 教授 (90232066)
|
Co-Investigator(Kenkyū-buntansha) |
NODA Yukio 東北大学, 多元物質科学研究所, 教授 (80127274)
ISHIHARA Sumio 東北大学, 大学院・理学研究科, 教授 (30292262)
KAJIMOTO Ryoichi 独立行政法人日本原子力研究開発機構, 量子ビーム応用研究部門, 研究員 (30391254)
|
Co-Investigator(Renkei-kenkyūsha) |
KIMURA Tsuyoshi 大阪大学, 大学院・基礎工学研究科, 教授 (80323525)
SAGAYAMA Hajime 東京大学, 大学院・新領域創成科学研究科, 助教 (90436171)
ABE Nobuyuki 東京大学, 大学院・新領域創成科学研究科, 助教 (70582005)
|
Project Period (FY) |
2007 – 2011
|
Project Status |
Completed (Fiscal Year 2011)
|
Budget Amount *help |
¥124,800,000 (Direct Cost: ¥124,800,000)
Fiscal Year 2011: ¥17,100,000 (Direct Cost: ¥17,100,000)
Fiscal Year 2010: ¥23,700,000 (Direct Cost: ¥23,700,000)
Fiscal Year 2009: ¥28,600,000 (Direct Cost: ¥28,600,000)
Fiscal Year 2008: ¥29,400,000 (Direct Cost: ¥29,400,000)
Fiscal Year 2007: ¥26,000,000 (Direct Cost: ¥26,000,000)
|
Keywords | 強相関電子系 / 磁気記録 / 磁性 / 低温物性 / 強誘電体物性 |
Research Abstract |
Many accomplishments on magnetic ferroelectrics have been obtained. The mechanism of magnetic-field-induced 90-degree rotation of electric polarization has been elucidated by experimental and theoretical investigations. Based on the knowledge, new magnetic ferroelectrics including a room-temperature multiferroic have been developed. As for the giant magneto-electric effects, the reversal in electric polarization induced by a fine tuning of magnetic field direction has been achieved. We have also succeeded in controlling the magnetization direction in CuB_2O_4 as well as the helicity in several helimagnets with the application of an electric field. The low-energy excitation in a representative spin-driven ferroelectric TbMnO_3 has been also studied by inelastic x-ray and neutron scattering as well as THz-light absorption, which provides useful information about the electro-magnons. Through theoretical studies, we propose a new mechanism of spin-driven ferroelectricity. We have also found a strong coupling between spin and ferroelectricity in a triangular lattice with charge-order instability.
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