RUI: Magnetic Tunneling and Relaxation in Single Molecule Magnets Examined Using Terahertz Spectroscopy

RUI：使用太赫兹光谱检查单分子磁体的磁隧道和弛豫

• 批准号: 0405576
• 负责人: Mary Parks
• 金额: --
• 依托单位: Colgate University
• 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: 2004-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0405576&HistoricalAwards=false
• 关键词: RUI; Magnetic; Tunneling; Relaxation; Single

This project proposes to examine the causes and effects of quantum tunneling of the magnetic moment in single molecule magnets. Quantum tunneling of the magnetic moment of Mn12-acetate was first reported in 1996, but its mechanism is still uncertain. This project will use a time-domain terahertz spectroscopy to probe a collection of these molecules during the tunneling process in order to provide a link between the local environment of the molecules and the tunneling probability. In a separate experiment, the process of relaxation will be observed through the observation of the THz pulse emitted when the molecules are suddenly heated above the blocking temperature, and it is anticipated that superradiance will be observed. This research award supports undergraduate research both directly through research stipends and indirectly through bringing this exciting research project to a liberal arts college. The involvement of undergraduate students in research increases the likelihood that they will pursue advanced degrees in science and will contribute to our nation's scientific infrastructure.Quantum tunneling is one of the hallmarks of quantum mechanics; its occurrence in a material guarantees that this material's properties cannot be explained by classical mechanics alone. In the twentieth century, the properties of very small quantum mechanical systems like atoms became fairly well understood. Now physicists are attempting to understand what happens when quantum mechanics becomes important for larger systems. This project hopes to expand our understanding of quantum mechanical tunneling in the material Mn12-acetate, in which clusters of atoms behave as nanoscale magnets that can tunnel from one orientation to another. Besides being of fundamental scientific interest, this line of research may also lead to denser memory storage for computers or even to quantum computers. These possible future applications make these experiments particularly exciting for undergraduate physics students. This research award supports undergraduate research both directly through research stipends and indirectly through bringing this exciting research project to a liberal arts college. The involvement of undergraduate students in research increases the likelihood that they will pursue advanced degrees in science and will contribute to our nation's scientific infrastructure.

本项目拟研究单分子磁体中磁矩量子隧穿的原因和影响。1996年首次报道了Mn12-acetate磁矩的量子隧穿现象，但其机制尚不明确。该项目将使用时域太赫兹光谱在隧穿过程中探测这些分子的集合，以提供分子的局部环境与隧穿概率之间的联系。在一个单独的实验中，将通过观察当分子突然加热到阻挡温度以上时发射的太赫兹脉冲来观察弛豫过程，并预计将观察到超辐射。这个研究奖通过研究津贴直接支持本科生的研究，也通过将这个令人兴奋的研究项目带到文理学院来间接支持本科生的研究。本科生参与研究增加了他们追求科学高级学位的可能性，并将为我们国家的科学基础设施做出贡献。量子隧穿是量子力学的标志之一；它在材料中的出现保证了这种材料的性质不能仅仅用经典力学来解释。在20世纪，像原子这样的非常小的量子力学系统的性质得到了相当好的理解。现在，物理学家正试图理解当量子力学对更大的系统变得重要时会发生什么。这个项目希望扩大我们对mn12 -醋酸盐材料中量子力学隧穿的理解，在这种材料中，原子簇的行为就像纳米级磁铁，可以从一个方向隧穿到另一个方向。除了具有基础科学兴趣外，这条研究路线还可能导致计算机甚至量子计算机的更密集内存存储。这些可能的未来应用使得这些实验对物理学本科生来说特别令人兴奋。这个研究奖通过研究津贴直接支持本科生的研究，也通过将这个令人兴奋的研究项目带到文理学院来间接支持本科生的研究。本科生参与研究增加了他们追求科学高级学位的可能性，并将为我们国家的科学基础设施做出贡献。