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

磁性稀土离子(例如，三重电离的Ho)在低浓度下引入到单晶氟化锂中，形成了一类被称为单离子磁体的纳米材料。这些系统是相对较新的，并展示了与Ho离子的耦合电核态相关的各种令人着迷的磁现象。这些系统不仅在科学上很有趣，而且对量子计算机的Q比特的开发和高密度磁记录介质的开发具有重要的技术相关性。该项目使用核磁共振、µ子自旋共振和交流热测量来研究这些纳米磁铁。这些实验的结果将被用来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退相干，并表征磁关联的开始是随着偶极耦合强度的增加而增加的函数，而偶极耦合强度的增加会随着Ho离子浓度的变化而改变。该项目是意大利帕维亚大学、法国格勒诺布尔路易斯·内尔实验室和波士顿学院的研究小组合作开展的。此外，ISIS-Rutherford Appleton实验室(联合王国)和Paul Scherrer研究所(瑞士)的Muon用户设施将用于开展拟议研究的部分工作。通过样品制作和理论分析为该项目提供了额外的科学支持，俄罗斯瓦维洛夫光学研究所和喀山国立大学的同事分别参与了该项目。因此，拟议的工作将为美国研究生和本科生提供特殊的教育机会，方法是延长对上述一些实验室的研究访问，并参加欧洲设施的核磁共振和Muon光谱学的正式培训讲习班。此外，美国的初级研究人员将在分子磁学领域获得宝贵的经验，并熟悉Muon自旋光谱技术，这是美国目前代表性较低的领域。该奖项由材料研究部门和国际科学与工程办公室共同支持。

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.