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

这项建议是为了扩大合作研究的努力， 位于彼得堡的约费研究所的俄罗斯研究小组 以及美国格鲁吉亚大学的激光光谱学小组。 单晶光纤中声子动力学的电流合作 将扩大到包括玻璃中声子的动力学， 应用高分辨率激光光谱技术， 铁电体的研究。 拟议中的研究将与俄罗斯的专业知识相匹配 声子动力学和铁电体光谱学的研究者 拥有最先进的激光设备和专业知识 格鲁吉亚大学的光谱学。 这些设施 包括用于制备单晶纤维的系统 利用激光加热基座生长技术， 单色声子可调谐脉冲远红外激光器 产生和单频可调谐染料激光器的相干 瞬态和光谱烧孔光谱学。 这项研究工作的预期结果将提供 信息的域结构和光学的可能性 掺铬锂铁电体烧孔存储器 使用光子选通光电离烧孔的锗酸盐玻璃， 关于空间、光谱和时间声子动力学的信息 更好地理解声子表面 晶体中的相互作用和声子输运 单晶纤维的几何形状。 %%% 本研究涉及材料科学中的三个基本问题。 的 第一个项目将是研究高频率的动态 无序材料如玻璃中的声子。 这个问题 涉及对热传输、结构和 玻璃态系统的动力学 第二个项目将是 研究铁电材料的电畴结构， 最先进的高分辨率激光光谱仪 的结果 演习应提供新的信息的基本 铁电材料的性能。 最后，铁电 将对含有已知杂质的材料进行研究， 高密度光学计算机存储器的可能的新候选者 使用持续的光学烧孔。 这项研究将是 作为美国激光器之间的合作努力进行 格鲁吉亚大学光谱学小组和俄罗斯 彼得堡约费研究所的研究小组。 它将 利用格鲁吉亚大学的专业知识和设施 在高分辨率激光光谱学中，远红外激光和 使用激光加热基座的材料制备能力 增长，再加上在Ioffe研究所的专业知识， 铁电体的性质、制备方法及其经验 用玻璃研究声子。

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.