Transient Optical Studies of Non-equilibrium Excitations in Semiconductors and Energy Transfer Processes in Ionic Crystals

9301100 Tsen这个实验计划将研究极端非平衡条件下半导体中载流子的动力学。第二个子项目将研究离子晶体中的能量传递过程。亚皮秒时间分辨拉曼光谱将被用来研究电场下的载流子输运。这项技术提供了对实验结果的直接、简单的解释，这将提供关于弹道传输和纳米结构半导体中理论预测的速度过冲现象的确凿的基本信息。用时间分辨拉曼光谱研究离子晶体中的各种能量传递过程，可以提供关于固体模型体系中振动到振动能量传递过程的直接信息。这个实验项目将研究半导体电子在强电场影响下的运动动力学。第二个项目将研究当离子晶体吸收光时，能量是如何在各种振动模式之间传递的。这些信息具有基础性意义，也具有技术意义。它将有助于设计更好、更快的微米和亚微米尺寸的半导体器件。能量传递过程直接关系到用于光子学和电信应用的远红外激光器的设计和使用。***

9301100 Tsen This experimental program will study the dynamics of carriers in semiconductors under extreme non-equilibrium conditions. A second sub-project will investigate energy transfer processes in ionic crystals. Sub-picosecond time-resolved Raman spectroscopy will be used to examine carrier transport under electic fields. The technique provides a direct, simple interpretation of the experimental results, which will provide conclusive fundamental information on ballistic transport as well as velocity overshoot phenomena predicted theoretically in nanostructured semiconductors. Study of various energy transfer processes in ionic crystals by time-resolved Raman spectroscopy should provide direct information about vibrational-to-vibrational energy transfer processes in a model solid state system. %%% This experimental program will study the dynamics of semiconductor electrons moving under the influence of high electric fields. A second project will investigate how energy is transferred among the various modes of vibration in an ionic crystal when it absorbs light. The information is of fundamental significance and is also of technological significance. It will aid in the design of better and faster semiconductor devices of micron and submicron dimensions. The energy transfer processes are immediately relevant to the design and utility of far infrared lasers used in photonics and telecommunications applications. ***