二维过渡金属硫化物的光电子特性及其外场调控

项目名称： 二维过渡金属硫化物的光电子特性及其外场调控

项目编号： No.61504043

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 李文武

作者单位： 华东师范大学

项目金额： 22万元

中文摘要： 研究材料的基本物理特性是推动新型电子器件应用的基础。本项目以新型二维层状过渡金属硫化物MX2(M为过渡金属，X为硫族元素)及其掺杂材料作为研究体系。通过采用拉曼、光致发光、椭圆偏振和红外磁光光谱等多种凝聚态光谱技术，建立外场(温度场、电场和磁场等)对二维过渡金属硫化物光电子特性的调控方法。系统研究该体系的微观电子能带结构、介电函数和光学带隙等性质与材料层数、温度场和电场之间的依赖关系。通过温度场调控不同层数硫化物的晶格振动和光致发光特性，澄清其声子-电子耦合和光电跃迁的物理起源。发展变温和变磁场下的光电评价手段，通过偏振光与电荷极化取向的耦合，探索材料激子跃迁、电荷极化和自旋等效应与外加磁场和温度场的耦合规律。发展介电响应理论分析方法，合理解释外场调控二维过渡金属硫化物光电子特性的物理机理，为基于二维过渡金属硫化物的电子器件的应用提供实验依据和理论支持。

中文关键词： 光学性质；二维过渡金属硫化物；外场调控；电子能带结构

英文摘要： The investigations of physical properties in novel materials play a key role in the applications of new-type electronic device. In this proposal, two-dimensional layered transition metal dichalcogenides (TMDs) MX2 ( M is a transition metal element, X is a chalcogen element) and its alloys will be selected as the research target. Using the Raman spectroscopy, photoluminescence spectroscopy, spectroscopic ellipsometry, and infrared magneto-optic spectroscopy, the methods related external field (temperature, electric, and magnetic field) manipulation on the optoelectronic properties of two-dimensional TMDs will be established. The relationship among electronic band structures, dielectric functions, optical band gap of the materials and the number of layer, temperature, magnetic field will be obtained. Based on the lattice vibrations and photoluminescence properties of TMDs under different layers and external field, the physical origins of phonon-electron coupling and optoelectronic transitions will be discussed. Furthermore, the research techniques for optoelectronic properties will be developed. Using the interaction between polarized light and electron polarization orientation, the coupling law among excitonic transition effects, electron polarization and spin effects and the magnetic field, temperature will be explored. The theoretical method for dielectric response analysis will be developed. The physical mechanisms related external field manipulation on the optoelectronic properties in two-dimensional TMDs will be explained. Our research results will provide an experimental evidence and theoretical support for the applications of electronic devices based on two-dimensional TMDs.

英文关键词： Optical properties;Transition metal dichalcogenides;External field manipulations;Electronic band structures