Spin-dynamics in Manganese and Iron Based Zinc-Selenide Magnetic Heterostructures

这个项目使用各种时间分辨光谱技术来阐明II-VI半导体中电子、空穴和磁性杂质之间以及杂质本身之间的交换相互作用的动力学。本研究的目的如下：(1)研究不同维构型下激子磁极化子的形成和衰变动力学；(2)测量锰掺杂锌-硒和铁掺杂锌-硒结构中锰-铁相互作用的相对强度和空间尺度；(3)光学测量磁自旋局部扰动的空间扩散，以获得磁性杂质之间交换相互作用的新信息。(4)直接测量价带混合对自旋弛豫速率的影响。% % % %最近使用硒化锌的蓝色固体激光器的发展增加了理解这些材料中基本相互作用的基本物理的需要。特别是，这些材料中高激发态的基本弛豫机制直接适用于新型高效激光二极管的工程设计。本项目将使用多种新颖的时间分辨光谱学来研究宽间隙锌-硒基半导体中电子空穴与磁性杂质之间的相互作用。特别是，我们希望了解这些材料中的自旋如何失去能量并最终形成新的限制态，以及这些材料中的磁相互作用如何影响电子和空穴的输运性质。＊＊＊

9409049 Smith This project uses a variety of time-resolved spectroscopic techniques to shed some light on the dynamics of the exchange interactions in II-VI semiconductors between electrons, holes and magnetic impurities, as well as among the impurities themselves. The goals of this research are the following: (1) to study the dynamics of formation and decay of exciton magnetic polarons in different dimensional configurations, (2) to measure the relative strength and spatial scale of the Manganese-Iron interaction in Manganese doped Zinc-Selenium and Iron doped Zinc-Selenium structure, (3) to measure optically the spatial diffusion of a local perturbation of the magnetic spins in order to gain new information on exchange interaction between the magnetic impurities, and (4) to measure directly the effect of valence band mixing on spin-relaxation rate. % % % % The recent development of blue solid state lasers using Zinc- Selenide has increased the need for understanding the basic physics of elementary interactions in these materials. In particular, the basic relaxation mechanisms of highly excited electronic states in these materials is directly applicable to the engineering of new higher-efficiency laser-diodes. This project will use a variety of novel time-resolved optical spectroscopies to study the interaction between electrons holes and magnetic impurities in wide-gap Zinc- Selenide-based semiconductors. In particular, we hope to gain understanding on how the spins in these materials lose energy and eventually form new confined states, as well as how the magnetic interactions in these materials affect the transport properties of electrons and holes. ***