Optical Dephasing of Ions in Solids and Studies of Phonon Dynamics

这项研究的目的是利用强大的远红外声子产生技术，结合灵敏和可调的光学探测方法，获得关于高频声子动力学的新信息。第二个项目涉及使用各种技术研究光学消相和光谱扩散，探测范围广泛的时间尺度。远红外缺陷诱导的单声子吸收允许产生可调谐的单能声子分布，当与使用振动边带声子光谱的可调谐探测相结合时，将允许真正的时间分辨声子光谱。这种光谱将被用来研究导致声子分裂和声子复合的非谐声子-声子相互作用。光学消相研究将利用时间域和频域的方法。特别值得注意的是确定均匀线宽的不同时间尺度的影响。这些结果将用电子自旋-自旋相互作用和电子-核自旋相互作用引起的退相的随机模型进行分析。还将开发计算机模拟。

This research has the purpose of obtaining new information on the dynamics of high frequency phonons using powerful far infrared phonon generation techniques coupled with sensitive and tunable optical detection methods. A second project involves the study of optical dephasing and spectral diffusion using a variety of techniques probing a wide range of time scales. Far infrared defect-induced one-phonon absorption permits generation of a tunable monoenergetic phonon distribution, which when combined with tunable detection employing vibronic sideband phonon spectroscopy, will permit truly time-resolved phonon spectroscopy. This spectroscopy will be used to study anharmonic phonon-phonon interactions responsible for phonon breakup and phonon recombination. The optical dephasing studies will utilize methods in both the time and frequency domain. Of special interest are the effects of different time scales for the determination of homogeneous line width. These results will be analyzed with stochastic models for the dephasing due to electron spin-spin and electron-nuclear spin interactions. Computer simulations will also be developed.