Materials World Network: Quantum Dynamics and Onset of Magnetic Correlations in Single-Ion Magnets

材料世界网络：单离子磁体中的量子动力学和磁相关性的开始

• 批准号: 0710525
• 负责人: Michael Graf
• 金额: $ 30.9万
• 依托单位: Boston College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0710525&HistoricalAwards=false
• 关键词: Materials; World; Network; Quantum; Dynamics

The magnetic rare-earth ions (for example, triply ionized holmium) introduced at small concentrations into single crystal Lithium Yttrium Fluoride, form a class of nanoscale materials called single-ion magnets. These systems are relatively new and exhibit a fascinating variety of magnetic phenomena associated with the coupled electro-nuclear states of the holmium ion. Not only are these systems scientifically interesting, but they possess important technological relevance for the development of q-bits for quantum computers and for the development of dense magnetic recording media. This project uses Nuclear Magnetic Resonance (NMR), muon spin resonance and AC thermal measurements to study these nanomagnets. The results from these experiments will be used to understand the spin dynamics and decoherence in this system via interactions with the surrounding atoms and to characterize the onset of magnetic correlations as a function of increasing dipolar coupling strength, which is changed by varying holmium ion concentration. Studies on a related interesting hybrid single-ion molecular magnet terbium di-pthalocyanine, will also be carried out.This project is a collaborative effort involving research groups at the University of Pavia, Italy, the Louis Néel Laboratory in Grenoble, France, and Boston College. In addition, the muon user facilities at ISIS - Rutherford Appleton Laboratory (UK), and the Paul Scherrer Institute (Switzerland) will be used to carry out parts of the proposed research. Additional scientific support for the project through sample fabrication and theoretical analysis involves colleagues at the Vavilov Optical Institute and Kazan State University in Russia, respectively. Thus the proposed work will provide US graduate and undergraduate students with exceptional educational opportunities through extended research visits to some of the above laboratories and by participation in formal training workshops for NMR and muon spectroscopy at European facilities. Furthermore, the US junior researchers will gain valuable experience in the field of molecular magnetism, and become familiar with techniques of muon spin spectroscopy, areas in which the US is currently under-represented.This award is co-supported by the Division of Materials Research and the Office of International Science and Engineering.

磁性稀土离子（例如，小浓度）以少量浓度引入单晶锂氟化物中，形成一类称为单离子磁铁的纳米级材料。这些系统是相对较新的，并且表现出与Holmium Ion的耦合电核状态相关的各种磁现象。这些系统不仅在科学上很有趣，而且在开发量子计算机的Q位和致密磁记录介质的开发方面具有重要的技术相关性。该项目使用核磁共振（NMR），MUON自旋共振和AC热测量测量来研究这些纳米磁铁。这些实验的结果将用于通过与周围原子的相互作用来理解该系统中的自旋动力学和破坏性，并表征磁相关性的发作，这是增加偶性偶联强度的函数，这会通过不同的Holmium离子浓度来改变。有关相关兴趣的研究混合单位分子磁铁Terbium Di-pthalocyanine也将进行。该项目与意大利帕维亚大学的研究小组，意大利大学的路易斯·涅尔大学实验室，格伦布尔，法国，法国和波士顿学院的研究小组。此外，ISIS-卢瑟福·阿普尔顿实验室（英国）和保罗·舍尔学院（瑞士）的MUON用户设施将用于进行拟议的研究的一部分。通过样本制造和理论分析对项目的额外科学支持分别涉及俄罗斯Vavilov光学研究所和喀山州立大学的同事。拟议的工作将通过对上述某些实验室的扩展研究以及参加欧洲设施的NMR和MUON光谱的正式培训研讨会，从而为我们提供毕业生和本科生的教育机会。此外，美国初级研究人员将在分子磁性领域获得宝贵的经验，并熟悉MUON自旋光谱技术的技术，该领域目前代表性不足。该奖项由材料研究部和国际科学和工程局共同支持。