Gigantic magnetoelectric effect in ferroelectric-magnets

铁电磁体中的巨大磁电效应

• 批准号: 17340104
• 负责人: TOKURA Yoshinori
• 金额: $ 10.66万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17340104/
• 关键词: Magnetoelectric effect; Ferroelectrics; Ferromagnets; Cross-correlation; Strongly-correlated electronics; Magnetic ferroelectrics; 誘電体; 誘電体物性; 磁性; 光学的電気磁気効果; 電気分極フロップ; スパイラル、ヘリカル磁気構造; マンガン酸化物

In this study we have developed the magnetic ferroelectric oxides which may host the gigantic magnetoelectric effect. We could control the electric polarization in the materials by magnetic field as the gigantic magnetoelectric effect, and some times the magnetic structure itself by electric field as the reciprocal effect. The gigantic optical magnetoelectric (magneto-chiral) effect was also observed.We have aimed at the realization of the gigantic magnetoelectric effect, and found new magnetic ferroelectrics based on the time and space symmetry breaking, multicriticality of electronic phases, and the chirality in lattices and frustration of spins. We have found magnetic ferroelectricity in perovskite type manganites RMnO_3 and Pr(Sr, Ca)_2Mn_2O_7, spinets CoCr_2O_4, and low dimensional frustration oxides Cu(Fe, Al)O_2, and LiCu_2O_2, in which polarization was controlled by magnetic field. Furthermore the change of the magnetic chirality with external electric field was confirmed by synchrotron x ray radiation, and neutron scattering studies.The gigantic optical magnetoelectric effect has various potentials for the new optical devices such as an optical isolator in the optical communication. We have succeeded in the synthesis of the single crystals of the rare earth metal doped (Ba, Sr)TiO_3, La_2Ti_2O_7 and so on, and observed the emission spectra due to the optical magnetoelectric effect. Moreover, we observed the optical magnetoelectric response stem from the magnetic interface of the tailor-made tricolor superlattice of LaMnO_3/SrMnO_3/LaAlO_3.In collaboration with theory groups, we show the origins of these effects are the unconventional magnetoelectric coupling characterized by the quantities of spin current and toroidal moment. We believe that this made a great contribution to the progress of the new spintronics.

在本研究中，我们开发了具有巨大磁电效应的磁性铁电氧化物。我们可以通过磁场来控制材料中的电极化，即巨大的磁电效应，有时也可以通过电场来控制磁性结构本身，即相互作用。还观察到巨大的光磁电（磁手性）效应。我们以实现巨大磁电效应为目标，基于时空对称性破缺、电子相的多临界性、晶格中的手性和自旋的受挫性，发现了新的磁性铁电体。在钙钛矿型锰矿RMnO_3、Pr(Sr, Ca)_2Mn_2O_7、尖晶石CoCr_2O_4和低维挫折氧化物Cu(Fe, Al)O_2、LiCu_2O_2中发现了磁性铁电，其极化受磁场控制。此外，通过同步加速器x射线辐射和中子散射研究证实了磁手性随外加电场的变化。巨大的光磁电效应为光通信中的光隔离器等新型光学器件提供了广阔的应用前景。我们成功地合成了稀土金属掺杂（Ba, Sr）TiO_3， La_2Ti_2O_7等的单晶，并观察了由于光磁电效应而产生的发射光谱。此外，我们还在LaMnO_3/SrMnO_3/LaAlO_3三色超晶格的磁性界面上观察到了光磁电响应。在与理论小组的合作中，我们证明了这些效应的起源是非常规的磁电耦合，其特征是自旋电流和环向矩的数量。我们认为这对新自旋电子学的发展做出了巨大的贡献。

项目成果

Nature of the transition between a ferromagnetic metal and a spin-glass insulator inyrochlore molybdates

铁磁金属与自旋玻璃绝缘体铬钼酸盐之间转变的性质

• 发表时间: 2007
• 期刊: Phys.Rev.Lett 99
• 作者: N.Hamsaki;K.Watanabe;T.Ohtsuka;I.Kezsmarki;S.Iguchi;S.Miyasaka;Y.Tokura
• 通讯作者: Y.Tokura

Mutual Control of Magnetism and Electricity in Multiferroics

多铁性材料中磁电的相互控制

• 发表时间: 2007
• 作者: T. Kimura;G. Lawes;T. Goto;Y. Tokura;A. P. Ramirez;D.Higashiyama;J.Fujioka;T.Kimura;Y. Tokura;十倉 好紀;Y. Tokura;十倉 姓紀;Y. Tokura;Y. Tokura;十倉 好紀;Y. Tokura;Y. Tokura;Y. Tokura;十倉好紀;Y. Tokura;Y. Tokura
• 通讯作者: Y. Tokura

Multiferroics - From Frustrated Lattice to Tailored Interface

多铁性 - 从受挫晶格到定制界面

• 发表时间: 2007
• 作者: T. Kimura;G. Lawes;T. Goto;Y. Tokura;A. P. Ramirez;D.Higashiyama;J.Fujioka;T.Kimura;Y. Tokura;十倉 好紀;Y. Tokura;十倉 姓紀;Y. Tokura;Y. Tokura;十倉 好紀;Y. Tokura;Y. Tokura;Y. Tokura;十倉好紀;Y. Tokura;Y. Tokura;Y. Tokura;Y.Tokura;Y. Tokura;Y. Tokura
• 通讯作者: Y. Tokura

Gigantic electromagnetic coupling in transition metal oxides

过渡金属氧化物中的巨大电磁耦合

• 发表时间: 2006
• 作者: T. Kimura;G. Lawes;T. Goto;Y. Tokura;A. P. Ramirez;D.Higashiyama;J.Fujioka;T.Kimura;Y. Tokura;十倉 好紀;Y. Tokura;十倉 姓紀;Y. Tokura;Y. Tokura;十倉 好紀;Y. Tokura;Y. Tokura;Y. Tokura;十倉好紀;Y. Tokura;Y. Tokura;Y. Tokura;Y.Tokura;Y. Tokura;Y. Tokura;Y. Tokura;Y. Tokura;十倉好紀;Y. Tokura;Y. Tokura;Y. Tokura;Y. Tokura;Y. Tokura;Y. Tokura;Y. Tokura
• 通讯作者: Y. Tokura

Gigantic Kerr rotation induced by a d-d transition resonance in M Cr 2 S 4 (M=Mn,Fe)

• DOI: 10.1103/physrevb.72.155114
• 发表时间: 2005-10
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: K. Ohgushi;T. Ogasawara;Y. Okimoto;S. Miyasaka;Y. Tokura;Y. Tokura