Nature of Quantum Localization Probed by Exciton Dynamics in II-VI Semiconductor Alloys

小行星9408816 技术摘要：提出研究II-VI族半导体合金中安德森局域化的性质。 在合金中，光生电子-空穴对或激子在迁移率边缘附近的寿命与其局域化长度直接相关。 因此，这些材料中的激子系统代表了研究量子局域化的模型系统。 激子局域化的动力学将通过时间分辨光致发光光谱来探测。 激子局域化长度，迁移率边缘，和局域化长度的临界指数将在不同的条件下，包括温度和合金无序度进行测量。 临界指数的普遍性和载流子局域化和激子局域化之间的根本区别将被研究。 这些研究为量子局域化物理提供了新的视角. 非技术摘要：固体中的无序能引起一种显著的效应，即电荷的空间局域化，称为安德森局域化。 由于圆顶无序度几乎是真实的材料的普遍特征，因此安德森局域化同样是决定凝聚态物质的电学、光学和其他物理性质的普遍成分。 因此，安德森定域化被认为是凝聚态物理中最重要的课题之一。 本研究拟研究在光电器件中具有重要应用的某些半导体合金（含有周期表第II族和第VI族元素）中的安德森局域化特性。 ***

9408816 Lin Technical abstract: It is proposed to investigate the nature of Anderson localization in II-VI semiconductor alloys. In the alloys the lifetime of a photogenerated electron-hole pair, or exciton, near the mobility edge is directly correlated to its localization length. Thus the exciton system in these materials represents a model system for studying quantum localization. The dynamics of exciton localization will be probed by time resolved photoluminescence spectroscopy. The exciton localization length, mobility edge, and the critical exponent of the localization length will be measured under different conditions including temperature and the degree of alloy disorder. The universality of the critical exponent and the fundamental differences between charge carrier localization and exciton localization will be investigated. These studies can provide new insight into the physics quantum localization. Non-technical abstract: Disorder in solids can cause a remarkable effect that is the spatial localization of electronic charge, which is called Anderson localization. Since dome degree of disorder is a nearly universal feature of real materials, the Anderson localization is likewise a ubiquitous ingredient in determining electrical, optical, and other physical properties of condensed matter. Therefore, Anderson localization is recognized as one of the most important subjects in condensed matter physics. This proposed research is to study the properties of Anderson localization in certain semiconductor alloys (containing elements from groups II and VI of the periodic table) which have important applications in optoelectronic devices. ***