Materials and Thin Films for Spintronic Devices

该项目将致力于III-V稀磁半导体(III-V DMS)三元化合物的生长，其中的阴离子与3D-过渡族的成员进行置换。该计划的动机和目标是探索和建立成功生长单晶的条件，这些单晶将成为研究3D跃迁离子(3D-TMI)大磁矩(3D-TMI)产生的超常物理现象及其受主作用的材料。自由空穴的同时存在和大的磁矩为与自旋极化载流子相关的新现象提供了依据。最初的生长将集中在通过热扩散和熔体生长的方式在GaP、GaP和InSb中掺入Mn、Co和Fe。普渡大学的光谱(傅立叶变换红外光谱、拉曼光谱和光致发光光谱、调制反射/透射率和磁光表征)以及国际合作者基于磁学、电子顺磁共振和非线性光谱学的研究将为晶体生长提供宝贵的反馈。另一项合作将涉及高纯起始材料的生产和适用于分子束外延(MBE)的衬底的制造。基础科学和与装置有关的工作将在这一阶段启动。除了由Co-PI实施的晶体生长计划外，学生还将参与表征活动，并将获得对生长技术的健康欣赏。这种接触和参与将使他们为21世纪的科学/技术劳动力做好准备。该计划的目的是为我们正在进行的振动、电子和磁特性的集体和局域激发的研究提供具有良好特性的III-V稀磁半导体的“稳态”供应。获得大块单晶以及分子束外延生长的外延层和量子阱结构的材料将给与会者带来在器件应用中具有重要意义的基础研究的强烈兴奋。

The project will be devoted to the growth of III-V diluted magnetic semi-conductors (III-V DMSs) ternary compounds in which the anions are re-placed with a member of the 3d-transition group. The motivation and goal ofthe program are to explore and establish the conditions for successful growthof single crystals which will be materials suitable for investigating the ex-traordinary physical phenomena originating in the large magnetic momentsof 3d-transition-ion (3d-TMI) and their role as acceptors. The simultaneouspresence of free holes and the large magnetic moments provide the ingredi-ents for novel phenomena associated with spin-polarized charge carriers. Thegrowth will initially focus on the incorporation of Mn, Co and Fe into GaAs,InP, GaP and InSb by thermal diffusion and melt growth. Spectroscopic(Fourier Transform Infrared, Raman and photoluminescence, modulated re-flectivity/transmission and magneto optic characterization at Purdue andthose based on magnetic, electron-paramagnetic-resonance, and non-linearspectroscopy by international collaborators will provide invaluable feedbackto the crystal grower. Another collaboration will address the production ofultrapure starting material and fabrication of substrates suitable for molec-ular beam epitaxy (MBE). Basic science and device related work will be ini-tiated during this phase. Besides the crystal growth program implementedby the Co-PI, students will participate in the characterization activities andwill acquire a healthy appreciation of growth techniques. This exposure andinvolvement will prepare them for the scientific/technical workforce of the21st century. The aim of the program is to provide a "steady state-" supply of wellcharacterized III-V diluted magnetic semiconductors to our ongoing researchon collective and localized excitations of vibrational, electronic, and magneticcharacter. The access to bulk single crystals as well as material as MBE-grown epilayers and quantum well structures will give the participants theintense excitement of basic research significant in device applications.