Laser Pulse-Probe Techniques for Investigating Physical Processes of Ions in Solids

本研究项目利用激光光谱学技术研究了掺杂过渡金属和稀土离子的无机基质晶体的基本物理过程。所要研究的过程包括离子间的能量迁移和无辐射弛豫跃迁。将采用的实验技术包括四波混频实验、累积光子回波实验和脉冲探测瞬时吸收实验。除了描述固体中离子之间的能量迁移外，还将努力验证固体中离子四波混频信号来源的详细模型。这些测量将以亚皮秒范围内的实时测量为特色。还将采用单轴应力测量。人们希望更多地了解与固体中离子的激发态之间的无辐射弛豫相关的鲜为人知的过程。

This research project utilizes laser spectroscopy techniques to investigate fundamental physical processes in inorganic host crystals doped with transition metal and rare earth ions. The processes to be studied include energy migration among the ions and radiationless relaxation transitions. The experimental techniques to be employed include four-wave mixing, accumulated photon echos, and pulse-probe transient absorption experiments. An effort will be made to verify a detailed model for the origin of the four-wave mixing signal of ions in solids, in addition to characterizing the energy migration between these ions in solids. The measurements will feature real time measurements in the subpicosecond regime. Uniaxial stress measurements will also be employed. It is hoped to learn more about the poorly understood processes associated with radiationless relaxation among the excited states of the ions in solids.