半导体及其合金中影响电子自旋动力学的新因素

项目名称： 半导体及其合金中影响电子自旋动力学的新因素

项目编号： No.11504194

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 滕利华

作者单位： 青岛科技大学

项目金额： 21万元

中文摘要： 近两年，作为自旋电子学领域的新材料，半导体合金GaAsBi体现出重要的研究价值，本项目将以GaAs和GaAsBi两种典型的半导体和半导体合金为研究对象，提出半导体及其合金中影响电子自旋动力学的新因素，具体内容包括：测量常温和低温下GaAsBi中电子初始自旋极化度的过超能量依赖，以期在GaAsBi高过超能量态获得高的电子初始自旋极化度。在GaAs和GaAsBi的电子－轻空穴和电子－重空穴系统内，分别测量常温下电子自旋弛豫时间、低温下电子自旋相干弛豫时间及GaAsBi中电子g因子的过超能量依赖，以期发现轻、重空穴系统对电子自旋弛豫时间、自旋相干弛豫时间和g因子的不同影响，通过理论分析揭示轻、重空穴系统对电子自旋动力学和g因子具有不同影响的物理机理，提出影响电子自旋动力学的新因素：轻、重空穴系统，获得高过超能量态电子自旋弛豫和自旋相干弛豫的机制，揭示GaAs和GaAsBi中电子自旋动力学的异同。

中文关键词： 半导体合金；自旋极化；自旋弛豫；高过超能量态；轻；重空穴

英文摘要： In recent two years, as a new material for spintronics, semiconductor alloy GaAsBi embodies important research value. We will take two kinds of typical semiconductor and semiconductor alloy GaAs and GaAsBi as the research objects, the new factors that influence the spin dynamics in semiconductor and its alloy will be proposed. Specific contents are as follows: We will measure the excess energy dependence of the initial degree of electron-spin polarization in GaAsBi at room temperature and low temperature, respectively. We hope that higher degree of electron-spin polarization can be find at higher excess-energy levels. In electron-light-hole and electron-heavy-hole subsystems of GaAs and GaAsBi, we will measure the excess energy dependence of the electron-spin relaxation time, spin coherence relaxation time and g factor (in GaAsBi) at room temperature and low temperature, respectively. The different influence of light and heavy holes on electron-spin relaxation time, spin coherence relaxation time and g factor will be found, the physical mechanism of the different influence will also be studied. The new factors that influence the spin dynamics will be proposed. In addition, the spin relaxation mechanism and spin coherence relaxation mechanism of electrons with high excess energy will be found, we will also reveal the similarities and differences of the spin dynamics in GaAs and GaAsBi.

英文关键词： semiconductor alloy ;spin polarization;spin relaxation;high excess energy state;light and heavy hole