晶格应变对钙钛矿结构锡酸盐基稀磁半导体性质影响研究

项目名称： 晶格应变对钙钛矿结构锡酸盐基稀磁半导体性质影响研究

项目编号： No.11504356

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： 王建峰

作者单位： 中国计量大学

项目金额： 24万元

中文摘要： 钙钛矿结构氧化物和稀磁半导体因为蕴含丰富物理和具有重大应用潜力而受到关注。钙钛矿结构锡氧化物ASnO3(A=Ba, Sr 和Ca等)是宽禁带半导体，可以实现高迁移率，是全钙钛矿器件中透明导电电极的理想材料。近来有研究尝试制备基于ASnO3的稀磁半导体。考虑到晶格应变在全钙钛矿器件和稀磁半导体中普遍存在，加之ASnO3自身物理性质对晶格应变相当敏感，本项目拟系统研究晶格应变对ASnO3基稀磁半导体的影响。实验上，引入各种应变，综合运用X射线衍射、透射电镜、光电子能谱、拉曼光谱、吸收光谱、霍尔效应和磁性测量等多种手段，研究晶格应变对其结构、光学、电学和磁学等性质的影响；理论上，基于第一性原理计算，加载不同应变，研究其影响；通过实验与理论相结合阐明应变的作用规律和机制，获得应变调控的方法。本项目的顺利实施有助于澄清稀磁半导体磁性来源，也为基于ASnO3的器件提供理论与技术基础。

中文关键词： 钙钛矿结构锡氧化物；稀磁半导体；晶格应变

英文摘要： Due to their rich physics and their promising properties for application, perovskite oxides and dilute magnetic semiconductors have attracted much attention in recent years. Perovskite stannates ASnO3(A=Ba, Sr and Ca) are wide band gap semiconductors. The high mobility achieved in these materials makes them promising candidates for transparent conductive electrodes in all-perovskite devices. Recently, there have been many attempts to fabricate ASnO3-based dilute magnetic semiconductors and reported room-temperature ferromagnetism in them. Lattice deformation is ubiquitous in all-perovskite devices and dilute magnetic semiconductors. On the other hand, it has been found that the physical properties of undoped ASnO3 are sensitive to lattice strain. In this proposed project, we shall systematically investigate the influences of lattice deformation on the physical properties of ASnO3-based dilute magnetic semiconductors. Experimentally, lattice strain of different types and with various magnitudes would be introduced and the structural, optical, electrical and magnetic properties would be characterized in detail by using various techniques, including X ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectra, optical transmission spectra, Hall effect, magnetoresistance, magnetometry measurements and etc. The effects of lattice strain will also be explored by using first-principle calculation. The combination of experimental and theoretical studies shall reveal the effects of lattice strain in ASnO3-based dilute magnetic semiconductors and their underlying mechanisms. It would also provide a way for strain modulation. It is expected that the successful implementation of this project would be helpful for revealing the origin and mechanism of ferromagnetism in dilute magnetic semiconductors as well as providing a reference for the development of ASnO3-based devices.

英文关键词： perovskite stannates;dilute magnetic semiconductor;lattice deformation