Laser Spectroscopy Investigations of Dynamical Processes of Ions in Solids

本研究的目的是表征光活性离子掺杂和激光激发泵浦晶体的性质。研究工作分为两个重点领域：表征掺杂离子之间的长距离能量迁移特性和确定激发态之间的无辐射跃迁速率。在这项工作中使用的主要实验技术是四波混频（FWM）光谱。对于能量转移研究，这将由时间分辨选址（TRSS）光谱测量来补充，对于无辐射衰变研究，这将由皮秒脉冲探针测量和累积光子回波测量来补充。实验将在几种对激光应用很重要的铬掺杂晶体上进行。通过将这两个领域获得的信息相关联，将有可能开始对光泵浦激光材料的光谱动力学进行详细的了解。通过比较所研究的每种材料的结果，将有可能将这些特征与宿主晶体的性质联系起来。从这种详细、系统的研究中获得的知识对激光和电光技术的持续发展是重要的。

The goal of this research is to characterize the properties of crystals doped with optically active ions and pumped by laser excitation. The research can be divided into two thrust areas: characterizing the properties of long range energy migration among the doping ions and determining the rates of radiationless transitions between excited electronic states. The major experimental technique to be used in this work is four-wave mixing (FWM) spectroscopy. For the energy transfer studies this will be supplemented by time-resolved site-selection (TRSS) spectroscopy measurements, and for the radiationless decay studies this will be supplemented by picosecond pulse-probe measurements and by accumulated photon-echo measurements. The experiments will be performed on several chromium doped crystals that are important for laser applications. By correlating the information obtained in both of these areas, it will be possible to begin developing a detailed understanding of the spectral dynamics of optically pumped laser materials. By comparing the results obtained on each of the materials investigated, it will be possible to relate these characteristics to the properties of the host crystal. The knowledge gained from this type of detailed, systematic study is important to the continued development of laser and electro-optic technology.