Materials World Network: Quantum Phenomena in Atomic Hydrogen Stabilized in Solid Molecular Hydrogen

材料世界网：固体分子氢中稳定的原子氢的量子现象

• 批准号: 1209255
• 负责人: David Lee
• 金额: $ 42万
• 依托单位: Texas A&M University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1209255&HistoricalAwards=false
• 关键词: Materials; World; Network; Quantum; Phenomena

TECHNICAL SUMMARYThis Materials World Network project will be focus on two main thrusts: (i) further studies of H atoms in molecular H2 films as well as D atoms in D2 films at lower temperatures, and (ii) extension of the work on impurity-helium condensate samples to lower temperatures and higher concentrations. Techniques will be modified to attain higher concentrations of H and D atoms in an attempt to observe Bose-Einstein condensation (BEC) of H in H2 and Pauli paramagnetism in D and D2 films. The mm wave studies of H atoms at T 1 K in thin and thick films of molecular H2 will be continued, with emphasis on careful temperature dependence measurements of the magnetization for samples prepared under different conditions in order to identify the cause of the non-Boltzmann behavior of the populations of the two lowest hyperfine states previously observed below 1 K. In addition a quartz microbalance will be utilized to test for superfluid behavior at low temperatures, a manifestation of BEC. A search will be made for changes in the Raman Spectrum associated with BEC. The ongoing research will include further studies of impurity-helium condensates containing hydrogen atoms, deuterium atoms or mixtures of H and D atoms in and on clusters of Kr and other noble gases. X band pulsed and CW ESR will be employed to study the magnetic relaxation behavior and the distribution of H and D atoms in and around the nanoclusters.NON-TECHNICAL SUMMARYConfirmation of the occurrence of Bose-Einstein condensation for H atoms moving through a solid molecular hydrogen crystal would be an important example of Bose-Einstein condensation in a periodic structure. Furthermore, mixed samples of H and D atoms contained in molecular matrices are excellent systems for the study of low temperature chemical reactions through the process of exchange quantum tunneling. Studies of impurity- helium condensates composed of assemblages of nanoclusters tie in nicely with studies of other forms of soft condensed matter. The impurity-helium condensates provide a means of storing large amounts of chemical energy which is released when the atoms combine to form molecules. This Materials World Network project clearly crosses the boundary between physics and chemistry and may provide valuable clues for practical energy storage systems. Further advances in millimeter wave technology being developed for ultralow temperature magnetic resonance will be useful in many other areas of science. The collaborative programs will benefit greatly from extended visits of graduate students, post docs and senior researchers between the partner laboratories. This project is supported by the Condensed Matter Physics program and the Office of Special Programs in the Division of Materials Research.

材料世界网络项目将集中在两个主要方面：（i）在较低温度下进一步研究分子H2膜中的H原子以及D2膜中的D原子，以及（ii）将杂质氦冷凝物样品的工作扩展到较低温度和较高浓度。技术将被修改，以获得更高浓度的H和D原子，试图观察玻色-爱因斯坦凝聚（BEC）的H在H2和泡利顺磁性D和D2膜。毫米波研究的H原子在T1 K的薄膜和厚膜的分子H2将继续，重点是仔细的温度依赖性测量的磁化强度的样品制备在不同的条件下，以确定的原因的非玻尔兹曼行为的人口的两个最低的超精细状态以前观察到低于1 K。 此外，石英微量天平将用于测试低温下的超流体行为，这是BEC的一种表现。 将对与BEC相关的拉曼光谱的变化进行研究。 正在进行的研究将包括进一步研究氪和其他惰性气体团簇中或团簇上含有氢原子、氘原子或氢和氘原子混合物的杂质氦凝聚物。X波段脉冲和CW ESR将被用来研究磁弛豫行为和H和D原子在纳米团簇中及其周围的分布。非技术总结H原子通过固体分子氢晶体运动的Bose-Einstein凝聚的发生的确认将是周期性结构中Bose-Einstein凝聚的一个重要例子。此外，分子基质中H和D原子的混合样品是通过交换量子隧穿过程研究低温化学反应的优良系统。对由纳米团簇组合而成的杂质氦凝聚物的研究与对其他形式的软凝聚物质的研究很好地结合在一起。杂质氦冷凝物提供了一种储存大量化学能的方法，当原子联合收割机结合形成分子时，化学能被释放出来。 这个材料世界网络项目显然跨越了物理和化学之间的界限，可能为实用的储能系统提供有价值的线索。为超低温磁共振开发的毫米波技术的进一步发展将在许多其他科学领域中有用。 合作计划将大大受益于合作实验室之间的研究生，博士后和高级研究人员的长期访问。 该项目由凝聚态物理计划和材料研究部特别计划办公室支持。