IMR - RUI: Acquisition of a Magnet Cryostat for Terahertz Spectroscopy and Education

IMR - RUI：购买用于太赫兹光谱和教育的磁铁低温恒温器

• 批准号: 0414251
• 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: 2004-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0414251&HistoricalAwards=false
• 关键词: IMR; RUI; Acquisition; Magnet; Cryostat

This grant will fund the acquisition of a split-coil magnet cryostat that will be incorporated into an existing terahertz spectrometer. The initial experiments that will be performed using this spectrometer will 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. In the longer term, this instrument will be used to study a wide variety of effects ranging from spin density waves to superconductivity, and it will also be used in upper level courses in solid state physics and materials science.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. The acquisition of this cryostat will enable experiments that will increase 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 by allowing students at a liberal arts college to be involved in an exciting research project. It also will benefit students enrolled in upper level solid state physics and materials science courses by making it possible to perform laboratory experiments in a strong magnetic field so they can see directly the phenomena they are studying.

这笔赠款将资助购买一个分裂线圈磁铁低温恒温器，将被纳入现有的太赫兹光谱仪。 使用该光谱仪进行的初步实验将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Mn 12-acetate磁矩的量子隧穿，但其机制仍然不确定。 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和隧穿概率之间的联系。 在一个单独的实验中，将通过观察分子突然被加热到阻断温度以上时发出的THz脉冲来观察弛豫过程，预计将观察到超辐射。 从长远来看，这台仪器将用于研究从自旋密度波到超导性的各种效应，也将用于固体物理学和材料科学的高级课程。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，物理学家们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。 这种低温恒温器的获得将使实验能够增加我们对Mn 12-acetate材料中量子力学隧穿的理解，其中原子簇表现为纳米级磁体，可以从一个方向隧穿到另一个方向。 除了具有基本的科学兴趣外，这一研究领域还可能为计算机甚至量子计算机带来更密集的内存存储。 这些可能的未来应用使这些实验特别令人兴奋的本科物理学生。 该研究奖通过允许文科大学的学生参与令人兴奋的研究项目来支持本科生研究。 它还将使就读于高级固态物理和材料科学课程的学生受益，使他们能够在强磁场中进行实验室实验，这样他们就可以直接看到他们正在研究的现象。