Strain-induced high-temperature perovskite ferromagnetic insulator.
Strain-induced high-temperature perovskite ferromagnetic insulator.
复制标题
应变诱导高温钙钛矿铁磁绝缘体
DOI：
10.1073/pnas.1707817115
复制
发表时间：
2018-03-20
影响因子：
11.1
通讯作者：
Lu Y
中科院分区：
文献类型：
--
作者：
Meng D;Guo H;Cui Z;Ma C;Zhao J;Lu J;Xu H;Wang Z;Hu X;Fu Z;Peng R;Guo J;Zhai X;Brown GJ;Knize R;Lu Y
意义铁磁绝缘体是开发下一代无耗散量子自旋电子器件的必要元件。这类材料比较少见，目前没有化学掺杂的高对称性材料只能在16 K以下工作。在这里，我们证明了拉伸应变LaCoO 3薄膜是一个应变诱导的高温铁磁绝缘体。实验和第一性原理计算都表明，当组分接近化学计量比时，拉伸应变支持的铁磁性达到最强。当Co ~（2+）缺陷浓度达到10%左右时，这种现象消失。这一发现为此类材料的可用性、高工作温度和制造未来器件的高外延集成潜力提供了机会。铁磁绝缘体是许多新型磁性器件的必需材料，如无耗散量子自旋电子器件、磁性隧道结等。具有高居里温度和高对称结构的铁磁绝缘体是与普通单晶氧化物薄膜或衬底集成的关键。到目前为止，常用的铁磁绝缘体大多具有低对称性结构，与生长质量差和广泛的性能。少数已知的高对称性材料要么具有极低的居里温度（≤16 K），要么需要化学掺杂反铁磁基质。在这里，我们提出了令人信服的证据表明，拉应变下的LaCoO 3单晶薄膜是一种罕见的未掺杂的钙钛矿铁磁绝缘体，具有非常高的TC高达90 K。实验和第一性原理计算表明，拉伸应变诱导的铁磁性，不存在于散装LaCoO 3。铁磁性在接近化学计量比的结构中最强，当Co2+缺陷浓度达到约10%时消失。该研究的重大影响包括应变诱导高温铁磁绝缘体的演示，液氮温度过渡的成功提升，以及集成到大面积器件制造工艺中的高潜力。
Significance Ferromagnetic insulators are highly needed as the necessary components in developing next-generation dissipationless quantum-spintronic devices. Such materials are rare, and those high symmetric ones without chemical doping available so far only work below 16 K. Here we demonstrate a tensile-strained LaCoO3 film to be a strain-induced high-temperature ferromagnetic insulator. Both experiments and first-principles calculations demonstrated that the tensile-strain–supported ferromagnetism reaches its strongest when the composition is nearly stoichiometric. It disappears when the Co2+ defect concentration reaches around 10%. The discovery represents a chance for the availability of such materials, a high operation temperature, and a high epitaxial integration potential for making future devices. Ferromagnetic insulators are required for many new magnetic devices, such as dissipationless quantum-spintronic devices, magnetic tunneling junctions, etc. Ferromagnetic insulators with a high Curie temperature and a high-symmetry structure are critical integration with common single-crystalline oxide films or substrates. So far, the commonly used ferromagnetic insulators mostly possess low-symmetry structures associated with a poor growth quality and widespread properties. The few known high-symmetry materials either have extremely low Curie temperatures (≤16 K), or require chemical doping of an otherwise antiferromagnetic matrix. Here we present compelling evidence that the LaCoO3 single-crystalline thin film under tensile strain is a rare undoped perovskite ferromagnetic insulator with a remarkably high TC of up to 90 K. Both experiments and first-principles calculations demonstrate tensile-strain–induced ferromagnetism which does not exist in bulk LaCoO3. The ferromagnetism is strongest within a nearly stoichiometric structure, disappearing when the Co2+ defect concentration reaches about 10%. Significant impact of the research includes demonstration of a strain-induced high-temperature ferromagnetic insulator, successful elevation of the transition over the liquid-nitrogen temperature, and high potential for integration into large-area device fabrication processes.
登录
查看更多内容
影响因子：
56.9
作者：
Matsumoto, Y;Murakami, M;Koinuma, H
通讯作者：
Koinuma, H
影响因子：
64.8
作者：
Katmis, Ferhat;Lauter, Valeria;Moodera, Jagadeesh S.
通讯作者：
Moodera, Jagadeesh S.
影响因子：
8.6
作者：
Mahadevan, Priya;Kumar, Abhinav;Sarma, D. D.
通讯作者：
Sarma, D. D.
影响因子：
3.2
作者：
Mehta, Virat;Suzuki, Yuri
通讯作者：
Suzuki, Yuri
影响因子：
8.6
作者：
Haverkort, M. W.;Hu, Z.;Tjeng, L. H.
通讯作者：
Tjeng, L. H.