A U.S.-New Zealand Collaborative Study of the Infrared Properties of Crystals

美国-新西兰合作研究晶体的红外特性

基本信息

批准号：
8922841
负责人：
Albert Sievers
金额：
$ 0.85万
依托单位：
Cornell University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
1991
资助国家：
美国
起止时间：
1991-09-15 至 1995-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=8922841&HistoricalAwards=false
关键词：
U.S.New Zealand Collaborative Study

项目摘要

This award supports a visit by Dr. A.J. Sievers of the Laboratory of Atomic Physics & Materials Science Center of Cornell University to the University of Canterbury in Christchurch, New Zealand, to work with Dr. J.A. Campbell on a study of the infrared properties of glassy crystals. Glass crystals represent a new materials system in which the universal character of glass behavior in solids can be probed. Although X-ray diffraction shows that crystal retains its long range order in the glassy state, low temperature thermodynamic measurements show that an additional low energy spectrum appears identical to that found in glasses. Dr. Campbell proposes to grow and characterize glassy Ba(1-x)La(x)F(2+x) crystals where x is varied from 0.001 to 0.46 so that the glass parameter is altered in a systematic manner. Dr. Sievers proposes to carry out persistent IR spectral hole burning measurements on these systems to compare the concentration of low lying nonequilibrium states to the concentration of thermodynamic glassy states. This proposed application of the persistent IR spectral hole burning technique will provide a new methodology for investigating and quantifying the physical characteristics of the low lying states in glasses. These experiments may also lead to a new understanding of processes influencing optical materials applications such as the relaxation behavior of optical excitations in laser glasses and the permanence of high density optical storage in glassy hosts.

该奖项支持 A.J. 博士的访问康奈尔大学原子物理与材料科学中心实验室的Sievers前往新西兰基督城坎特伯雷大学与J.A.坎贝尔对玻璃晶体的红外特性的研究。玻璃晶体代表了一种新材料系统，可以探测固体中玻璃行为的普遍特征。尽管 X 射线衍射表明晶体在玻璃态下保留了其长程有序，但低温热力学测量表明额外的低能谱与玻璃中发现的相同。 Campbell 博士建议生长并表征玻璃状 Ba(1-x)La(x)F(2+x) 晶体，其中 x 从 0.001 变化到 0.46，以便系统地改变玻璃参数。 Sievers 博士建议对这些系统进行持续的红外光谱烧孔测量，以比较低位非平衡态的浓度与热力学玻璃态的浓度。所提出的持久红外光谱烧孔技术的应用将为研究和量化玻璃中低位态的物理特性提供一种新的方法。这些实验还可能导致人们对影响光学材料应用的过程产生新的理解，例如激光玻璃中光激发的弛豫行为以及玻璃基质中高密度光存储的持久性。