Cerium Ferromagnets at the Quantum Critical Point

处于量子临界点的铈铁磁体

• 批准号: 0433560
• 负责人: Zachary Fisk
• 金额: $ 14.96万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0433560&HistoricalAwards=false
• 关键词: Cerium; Ferromagnets; Quantum; Critical; Point

Control variables such as chemical composition, applied pressure and applied magnetic field can be used to change the low temperature state of many intermetallic compounds of the element Ce from antiferromagnetically ordered to non-magnetic. This is achieved through lowering the ordering temperature, using a control variable, to T = 0K, the so-called quantum critical point. The realization that the rarely found unconventional superconductivity occurs in many if not all cases in this quantum critical regime now brings to the study of highly correlated electronic materials a focussed avenue for exploring the deep and imperfectly known connection between magnetism and exotic superconductivity, physics strongly implicated in high Tc cuprtate materials. This individual investigator award supports a project that will extend these studies into ferromagnetic Ce materials, allowing exploration of new aspects of the physics involved. The investigation of new materials is a primary experimental strategy in this research, pursuing in particular structure/property correlations - the elusive goal of materials driven physics. In addition to training post doctoral fellows and graduate students in materials driven condensed matter research, undergraduate and high school students will be introduced in the laboratory to condensed matter research through single crystal growth of new materials. The graduate students and postdoctoral fellows involved with this research will gain the experience of performing research at national facilities and laboratories. In addition they will become more globally aware through participation in international collaborations.Almost magnetic metallic materials near absolute zero have properties differing from usual metals. Exotic superconductivity has been discovered in a number of such materials in the neighborhood of this so-called quantum critical point, superconductivity which appears closely associated with the incipient magnetism and which may be closely related to the superconductivity of high Tc cuprates. This individual investigator award supports a research project that will explore cerium ferromagnetic materials across the magnetic/non-magnetic boundary, a class of materials which has been little studied in this connection and which presents new aspects of the physics involved. The goals are to understand the deep tie between unconventional superconductivity and magnetism, learn how to discover new materials which express this physics and extend this understanding into the richer and vaster field offered by new transition metal materials with potential technical applications. Graduate students and post doctoral fellows will be trained how to use the variable of new materials to conduct condensed matter physics research. They will have the experience of performing research at national facilities and laboratories. In addition they will become more globally aware through participation in international collaborations. Undergraduate and high school students will be introduced to condensed matter physics through the synthesis of new materials.

控制变量，如化学成分，施加的压力和施加的磁场可以用来改变元素Ce的许多金属间化合物的低温状态从反铁磁有序的非磁性。这是通过使用控制变量将有序化温度降低到T = 0 K，即所谓的量子临界点来实现的。很少发现的非常规超导性发生在许多情况下，如果不是所有的情况下，在这个量子临界制度的认识，现在带来了高度相关的电子材料的研究，探索磁性和奇异的超导性之间的深层和不完全已知的联系，物理学强烈牵连在高Tc铜酸盐材料的集中途径。这个个人研究者奖支持一个项目，将这些研究扩展到铁磁Ce材料，允许探索所涉及的物理学的新方面。新材料的研究是本研究的主要实验策略，特别是追求结构/性能相关性-材料驱动物理学的难以捉摸的目标。除了在材料驱动的凝聚态研究中培养博士后研究员和研究生外，还将在实验室中向本科生和高中生介绍通过新材料的单晶生长进行凝聚态研究。 参与这项研究的研究生和博士后研究员将获得在国家设施和实验室进行研究的经验。 此外，他们还将通过参与国际合作来提高全球意识。接近绝对零度的几乎磁性金属材料具有与普通金属不同的性质。在这种所谓的量子临界点附近的许多材料中发现了奇异的超导性，超导性似乎与初始磁性密切相关，并且可能与高Tc铜酸盐的超导性密切相关。该个人研究者奖支持一个研究项目，该项目将探索磁性/非磁性边界上的铈铁磁材料，这是一类在这方面研究很少的材料，并提出了所涉及的物理学的新方面。目标是了解非常规超导性和磁性之间的深层联系，学习如何发现表达这种物理学的新材料，并将这种理解扩展到具有潜在技术应用的新过渡金属材料所提供的更丰富和更广阔的领域。培养研究生和博士后研究员如何利用新材料的变量进行凝聚态物理研究。他们将有在国家设施和实验室进行研究的经验。 此外，他们还将通过参与国际合作提高全球意识。 本科生和高中生将通过新材料的合成介绍凝聚态物理。