New correlated electronic states arising from strong spin-orbit coupling

强自旋轨道耦合产生的新相关电子态

• 批准号: EP/N034872/1
• 负责人: Andrew Boothroyd
• 金额: $ 62.19万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FN034872%2F1
• 关键词: New; correlated; electronic; states; arising

Magnetic phenomena pervade the world around us and are used in a huge variety of practical devices, ranging from nanoscale data storage devices through electric motors to plasma fusion reactors. At a fundamental level, magnetism in solids comes from the coordinated actions of many atomic magnets. The atomic magnetism originates from the intrinsic spin and the orbital motion of the electrons, and the relative importance of spin and orbital magnetism depends on the particular magnetic atom and its environment. This project concerns magnetism in oxides containing heavy metal atoms such as ruthenium, molybdenum, osmium and rhenium. These atoms have partially filled 4d or 5d electronic orbitals with a large spin-orbit interaction which strongly entwines the spin and orbital magnetism. Until recently, the study of magnetism in the presence of strong spin-orbit coupling was confined to f-electron systems, but today there is increasing focus on 4d and 5d systems, in which the greater mobility of the electrons results in a more diverse range of phenomena. In the past few years, a large number of theoretical predictions have appeared for magnetic systems with strong spin-orbit coupling, but very few have been confirmed empirically. The predictions include: (i) materials whose atoms have no magnetism when in isolation but develop magnetism through interactions with neighbouring atoms, (ii) anisotropic, bond-directional magnetic couplings resulting in novel propagating magnetic modes, (iii) quantum-mechanically entangled spin and orbital liquid states with exotic emergent quasiparticle excitations, (iv) metal-insulator transitions driven by spin-orbit enhanced magnetic correlations, and (v) unconventional superconductivity of doped electrons mediated by magnetic fluctuations. The programme of research aims to search for and study these and other novel magnetic phases in 4d and 5d oxides. A significant challenge will be the growth of high quality single crystals, which are essential as samples for the experiments. To overcome this challenge we have assembled two leading crystal growers with a vast amount of relevant expertise, as well as a Project Partner, Prof Yamaura, who brings additional capability in high pressure synthesis. We shall perform measurements to probe the novel spin-orbital states in the materials of interest using state-of-the-art techniques at international synchrotron and neutron facilities. We shall collaborate with staff at the facilities, including our Project Partners the Diamond Light Source and Paul Scherrer Institute, as well as the European Synchrotron Radiation Facility in Grenoble and the ISIS spallation neutron source, to perform the measurements and develop the necessary techniques. Finally, we shall work with our theory Project Partners at the University of Toronto and collaborators to develop a detailed understanding of the new electronic and magnetic states we will uncover.

磁现象遍布我们周围的世界，并用于各种各样的实用设备，从纳米级数据存储设备到电动机到等离子体聚变反应堆。从根本上说，固体的磁性来自于许多原子磁体的协调作用。原子的磁性来源于电子的内禀自旋和轨道运动，自旋磁性和轨道磁性的相对重要性取决于特定的磁性原子及其环境。该项目涉及含有重金属原子（如钌、钼、锇和铼）的氧化物的磁性。这些原子具有部分填充的4d或5d电子轨道，具有大的自旋-轨道相互作用，其强烈地缠绕自旋和轨道磁性。直到最近，在强自旋轨道耦合存在下的磁性研究仅限于f-电子系统，但今天越来越关注4d和5d系统，其中更大的电子迁移率导致更多样化的现象。在过去的几年中，出现了大量的理论预测的磁性系统与强自旋轨道耦合，但很少有被证实的经验。这些预测包括：（i）其原子在隔离时没有磁性但通过与相邻原子的相互作用而产生磁性的材料，（ii）各向异性的、键方向的磁耦合，导致新颖的传播磁模式，（iii）具有奇异出现的准粒子激发的量子机械纠缠自旋和轨道液态，（iv）由自旋-轨道增强的磁关联驱动的金属-绝缘体跃迁，以及（v）由磁涨落介导的掺杂电子的非常规超导性。该研究计划旨在寻找和研究4d和5d氧化物中的这些和其他新型磁相。一个重大的挑战将是高质量单晶的生长，这是必不可少的实验样品。为了克服这一挑战，我们召集了两名拥有大量相关专业知识的领先晶体种植者，以及一名项目合作伙伴Yamaura教授，他在高压合成方面具有额外的能力。我们将在国际同步加速器和中子设施中使用最先进的技术进行测量，以探测感兴趣的材料中的新自旋轨道状态。我们将与这些设施的工作人员合作，包括我们的项目合作伙伴钻石光源和保罗谢勒研究所，以及格勒诺布尔的欧洲同步辐射设施和ISIS散在中子源，以进行测量并开发必要的技术。最后，我们将与多伦多大学的理论项目合作伙伴和合作者一起工作，以详细了解我们将发现的新的电子和磁性状态。

项目成果

Momentum-resolved lattice dynamics of parent and electron-doped Sr2IrO4

• DOI: 10.1103/physrevb.100.085131
• 发表时间: 2019-04
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: C. D. Dashwood;H. Miao;J. G. Vale;D. Ishikawa;D. Prishchenko;V. Mazurenko;V. Mazurenko;R. Perry;G. Cao;A. D. L. Torre;F. Baumberger;A. Baron;D. McMorrow;M. Dean

Momentum-resolved lattice dynamics of parent and electron-doped Sr$_{2}$IrO$_{4}$

母体和电子掺杂 Sr$_{2}$IrO$_{4}$ 的动量分辨晶格动力学

• DOI: 10.48550/arxiv.1904.10391
• 发表时间: 2019
• 作者: Dashwood C

Inelastic Neutron Scattering Investigations of an Anisotropic Hybridization Gap in the Kondo Insulators: CeT₂Al₁₀ (T=Fe, Ru and Os)

近藤绝缘体中各向异性杂化能隙的非弹性中子散射研究：CeT₂Al₁₀（T=Fe、Ru 和 Os）

• DOI: 10.4028/www.scientific.net/ssp.257.11
• 发表时间: 2016
• 期刊: Solid State Phenomena
• 作者: Adroja D

Magnetotransport of single crystal Sm$_2$Ir$_2$O$_7$ across the pressure-induced quantum-critical phase boundary

单晶 Sm$_2$Ir$_2$O$_7$ 跨越压力诱导的量子临界相界的磁输运

• DOI: 10.48550/arxiv.2210.05641
• 发表时间: 2022
• 作者: Coak M