RUI: Rare Earth Ions in Glasses

RUI：玻璃中的稀土离子

• 批准号: 9701576
• 负责人: Richard Brundage
• 金额: --
• 依托单位: St. Cloud State University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9701576&HistoricalAwards=false
• 关键词: RUI; Rare; Earth; Ions; Glasses

9701576 Brundage This is a renewal project from an undergraduate institution. The proposed work is a study of the stability of trivalent and divalent ions in fluorophosphate glasses and the effect of valence on the coherence of excited states. The project is motivated by recent measurements of unusually long coherence times for trivalent europium in fluorophosphate glasses developed for high-power laser applications. The divalent europium ion is stable in this glass, but can be photoionized to the trivalent ion by intense UV light. The divalent ion is unusual for rare-earth ions, but is stable for ytterbium and samarium as well as europium in some crystals and glasses. We will investigate the stability of different valences, the photoionization process, and the coherence times of excited electronic states for these three ions in fluorophosphate glasses. %%% This is a renewal project for the study of the fluorescence of rare earth ions in glasses. Rare earth ions play an important role in many optical devices, such as lasers and optical memories. The ions absorb and emit light when they make transitions between different electronic states. The frequency bandwidth f these transitions is an important parameter in determining the performance of optical devices. The narrower the bandwidth the greater the storage capacity of an optical memory based on frequency coding of data. The PI recently discovered that the bandwidth of the emission of the rare earth europium can be decreased by starting with divalent ions and removing one electron by photoionization using intense UV light to produce trivalent ions. The PI will study europium and other rare earth ions that occur in the divalent state to determine the effect of photoionization on the bandwidth of optical transitions. ***

9701576 Brundage 这是一个本科院校的更新项目。 拟议的工作是研究氟磷酸盐玻璃中三价和二价离子的稳定性以及价态对激发态相干性的影响。 该项目的动机是最近测量了为高功率激光应用开发的氟磷酸盐玻璃中三价铕的异常长的相干时间。 二价铕离子在这种玻璃中是稳定的，但可以通过强烈的紫外光光电离成三价离子。 二价离子对于稀土离子来说是不常见的，但对于镱和钐以及某些晶体和玻璃中的铕来说是稳定的。 我们将研究氟磷酸盐玻璃中这三种离子的不同价态的稳定性、光电离过程以及激发电子态的相干时间。 %%% 这是研究玻璃中稀土离子荧光的更新项目。稀土离子在许多光学器件中发挥着重要作用，例如激光器和光学存储器。 当离子在不同电子态之间进行跃迁时，它们会吸收并发射光。 这些跃迁的频率带宽是决定光学器件性能的重要参数。 带宽越窄，基于数据频率编码的光存储器的存储容量就越大。 PI 最近发现，可以通过从二价离子开始，使用强紫外光进行光电离以产生三价离子来去除一个电子，从而降低稀土铕的发射带宽。 PI 将研究铕和其他二价态稀土离子，以确定光电离对光学跃迁带宽的影响。 ***