Laser Spectroscopy of Ferroelectrics and Dynamics of Phononsin Glasses and Crystalline Fibers

铁电体的激光光谱学以及声子玻璃和晶体光纤的动力学

• 批准号: 9307610
• 负责人: Richard Meltzer
• 金额: $ 6.5万
• 依托单位: University of Georgia Research Foundation Inc
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-08-01 至 1997-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9307610&HistoricalAwards=false
• 关键词: Laser; Spectroscopy; Ferroelectrics; Dynamics; Phononsin

This proposal is to extend a collaborative research effort between the Russian research group at the Ioffe Institute in St. Petersburg and the U.S. laser spectroscopy group at the University of Georgia. The current cooperation in phonon dynamics in single crystal fibers will be broadened to include the dynamics of phonons in glasses and into the application of high resolution laser spectroscopy to the study of ferroelectrics. The proposed research will match the expertise of the Russian investigators in phonon dynamics and spectroscopy of ferroelectrics with the state-of-the-art facilities and expertise in laser spectroscopy at the University of Georgia. These facilities include a system for the preparation of single crystalline fibers using the techniques of laser-heated pedestal growth, a line tunable pulsed far infrared laser for monochromatic phonon generation and a single frequency tunable dye laser for coherent transient and spectral hole-burning spectroscopy. The anticipated results for this research effort will provide information on the domain structure and the possibility for optical holeburning memories in the ferroelectric chromium doped lithium germanate glasses using photon-gated photoionization holeburning, information on the spatial, spectral and temporal phonon dynamics of glasses, and a better understanding of phonon-surface interactions and phonon transport in crystals using the special geometry of single crystalline fibers. %%% This study treats three basic problems in materials science. The first project will be to examine the dynamics of high frequency phonons in disordered materials such as glasses. This problem relates to the understanding of heat transport, the structure, and the dynamics of glassy systems. The second project will be to study the domain structure of ferroelectric materials using state- of-the-art high resolution laser spectroscopy. The results of this exercise should provide new information on the fundamental properties of ferroelectric materials. Finally, ferroelectric materials containing known impurities will be investigated as possible new candidates for high density optical computer memories using persistent optical holeburning. This research will be conducted as a collaborative effort between the U.S. laser spectroscopy group at the University of Georgia and the Russian research group at the Ioffe Institute in St. Petersburg. It will utilize the expertise and facilities at the University of Georgia in high resolution laser spectroscopy, far infrared lasers and materials preparation capabilities using laser heated pedestal growth coupled with the expertise at the Ioffe Institute in the properties and preparation of ferroelectrics and their experience with phonon studies in glasses.

该提案旨在扩大圣彼得堡约夫研究所的俄罗斯研究小组和乔治亚大学的美国激光光谱小组之间的合作研究工作。 当前在单晶光纤声子动力学方面的合作将扩大到包括玻璃中声子动力学以及高分辨率激光光谱在铁电体研究中的应用。 拟议的研究将把俄罗斯研究人员在声子动力学和铁电体光谱方面的专业知识与佐治亚大学激光光谱方面最先进的设施和专业知识相结合。 这些设施包括使用激光加热基座生长技术制备单晶纤维的系统、用于产生单色声子的线可调谐脉冲远红外激光器以及用于相干瞬态和光谱烧孔光谱的单频可调谐染料激光器。 这项研究工作的预期结果将提供有关使用光子门控光电离烧孔的铁电铬掺杂锂锗酸盐玻璃中的域结构和光学烧孔存储器的可能性的信息，有关玻璃的空间、光谱和时间声子动力学的信息，以及使用单晶纤维的特殊几何形状更好地理解晶体中的声子-表面相互作用和声子输运。 %%% 这项研究解决了材料科学中的三个基本问题。 第一个项目将是研究玻璃等无序材料中高频声子的动力学。 这个问题涉及对玻璃系统的热传输、结构和动力学的理解。 第二个项目将是利用最先进的高分辨率激光光谱研究铁电材料的磁畴结构。 这项研究的结果应该提供有关铁电材料基本特性的新信息。 最后，将研究含有已知杂质的铁电材料，作为使用持久光学烧孔的高密度光学计算机存储器的可能新候选材料。 这项研究将由美国佐治亚大学激光光谱学小组和俄罗斯圣彼得堡约夫研究所的研究小组合作进行。 它将利用佐治亚大学在高分辨率激光光谱、远红外激光器和使用激光加热基座生长的材料制备能力方面的专业知识和设施，以及约夫研究所在铁电体性能和制备方面的专业知识以及他们在玻璃声子研究方面的经验。