报告题目 | Ferromagnetism in non-magnetic materials |
报告人 | Prof. FENG Yuanping |
报告人单位 | Department of Physics, National University of Singapore |
报告时间 | 2014-11-17 |
报告地点 | 合肥微尺度物质科学国家实验室九楼会议室 |
主办单位 | 合肥微尺度物质科学国家实验室、国际功能材料量子设计中心 |
报告介绍 | 报告摘要:
Ferromagnetism in non-magnetic materials has attracted much attention. Many studies have been carried out to identify the origin of the unexpected ferromagnetism, and to explore potential applications of such materials. Following successful prediction of room temperature ferromagnetism in III-V and II-VI semiconductors doped with 2p light elements, we recently extended the same strategy to topological insulators. We demonstrate simultaneous magnetic and hole doping achieved with a single dopant, carbon, in Bi2Se3 by first-principles calculations. Carbon substitution for Se (CSe) results in an opening of a sizable surface Dirac gap (up to 82 meV), while the Fermi level remains inside the bulk gap and close to the Dirac point at moderate doping concentrations. Using a combined theoretical and experimental approach, we reveal the origin of the long-range ferromagnetic coupling in a series of MOFs, constructed from antiferromagnetic dimeric-Cu(II) building blocks. Room temperature ferromagnetism was also observed in Teflon tape (polytetrafluoroethylene) when it is mechanical stretched, cut or heated. Our first-principles calculations revealed that the room temperature ferromagnetism originates from carbon dangling bonds and strong ferromagnetic coupling between them.
报告人简介: |