Group IV Ferromagnetic Semiconductors: Fabrication, Structure and
Magnetic and Electrical Properties
向钢 教授
四川大学
时间：2021年9月3日(星期五)下午3:30
地点：2号楼303A室
内容简介：Diluted magnetic semiconductors based on group-IV materials are desirable for spintronic devices compatible with current silicon technology. In this talk, we will present the results of transition metal (Mn, Fe)-doped SiGe semiconductors fabricated by non-equilibrium preparation methods including rapid thermal annealing (RTA), ion-implantation, and spark plasma sintering (SPS). After the preparation, the transition metal-doped samples become ferromagnetic semiconductors, in which the Curie temperature increases with increasing Mn doping concentration and reaches up to 300 K. The data suggest that the ferromagnetism comes from the hole-mediated process and is enhanced by the tensile strain in the SiGe crystals. Meanwhile, the Hall effect measurement up to 33 T to eliminate or reduce the influence of anomalous Hall effect reveals that the hole mobility of the annealed samples is greatly enhanced and the maximal value is above 1000 cm2 V−1s−1, owing to the strain-induced band structure modulation. The TM-doped SiGe semiconductors with high Curie temperature ferromagnetism and high hole mobility may provide a promising platform for semiconductor spintronics.
报告人简介：向钢，四川大学物理学院教授，博士生导师，副院长。美国宾夕法尼亚州立大学物理系博士（2006），兰州大学材料系硕士（2001），兰州大学物理系学士（1998）。长期从事磁性半导体与固体量子结构的制备与性能研究，主持科技部重点研发课题、国家自然科学基金等项目10余项，发表论文100余篇。曾入选教育部新世纪优秀人才，并获得唐立新教学名师奖等荣誉。