Muon spin rotation/relaxation investigations of magnetism in superconductors and coordination polymers

超导体和配位聚合物中磁性的μ子自旋旋转/弛豫研究

• 批准号: 238307-2011
• 负责人: Sonier, Jeffrey
• 金额: $ 1.6万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=570391
• 关键词: Muon; spin; rotation; relaxation; investigations

This proposal will primarily utilize newly constructed muon surface beam lines and the beta-decay NMR facility at TRIUMF to: 1) investigate the role inhomogeneity plays in the mechanism of high-temperature superconductivity, 2) determine the relevance of newly discovered magnetism in the heavily overdoped regime of high-temperature superconductors, 3) characterize and optimize magnetic interactions in a series of novel coordination polymers that make use of cyanometallate building blocks, 4) investigate the pairing symmetry of iron-based superconductors via measurements in the vortex state, 5) investigate the role of magnetic flux penetration in RF losses of superconducting Nb cavities used for charged-particle accelerators, and 6) investigate surface magnetism in gold nanostructures. In addition we will continue the development of a hyperpolarized xenon gas NMR method as an exquisitely senstive probe of surface properties with the potential to discover novel behaviour that has practical device applications. The muon spin rotation/relaxation (muSR) technique is unique in its ability to locally probe magnetism in materials, and for this purpose Canada has recently invested heavily in the construction and operation of new muon beam lines at TRIUMF. This proposal will exploit these new muSR capabilities as either the only means to collect information or to complement data obtained by other methods. Primary themes of this proposal include understanding the importance of nanoscale inhomogeneity on the development of a room-temperature superconductor, and controlled assembly of molecular building blocks in a predictable way as a means of designing a new generation of advanced magnetic materials.

该提案将主要利用新建造的μ子表面束线和TRIUMF的β衰变NMR设施：1）研究不均匀性在高温超导机制中的作用，2）确定新发现的磁性在高温超导体的重度过掺杂区域中的相关性，3）表征和优化一系列利用氰基金属酸盐结构单元的新型配位聚合物中的磁相互作用，4）通过在涡旋状态下的测量研究铁基超导体的配对对称性，5）研究磁通量穿透在用于带电粒子加速器的超导Nb腔的RF损耗中的作用，（6）研究金纳米结构的表面磁性。此外，我们将继续开发超极化氙气NMR方法，作为表面性质的灵敏探针，有可能发现具有实际设备应用的新行为。 μ子自旋旋转/弛豫（muSR）技术在其局部探测磁的能力方面是独特的， 为此，加拿大最近投入巨资在TRIUMF建造和运营新的μ子束线。该提案将利用这些新的muSR功能作为收集信息的唯一手段或补充通过其他方法获得的数据。该提案的主要主题包括理解纳米级不均匀性对室温超导体发展的重要性，以及以可预测的方式控制分子构建块的组装，作为设计新一代先进磁性材料的一种手段。