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

点击翻译按钮获取中文摘要

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.