Topological Semimetals

发布时间:2015-04-09

 

报告人  方忠 研究员

 

个人简介:中国科学院物理研究所研究员、博士生导师,美国物理学会会士(APS Fellow)。1996年获华中理工大学博士学位,1996-2003年访问日本、美国,2003年物理研究所工作至今。主要从事于新奇量子现象和计算凝聚态物理方面的研究工作,共发表SCI论文120余篇,他引9000余次。曾获2008年国际理论物理中心ICTP奖,2011年中国科学院杰出科技成就奖,2011年求是杰出科技成就集体奖,2012年全球华人物理学会“亚洲成就奖”,2013年周培源物理奖,2013年国家自然科学一等奖,2014周光召基础科学奖。

 

报告内容:  Topological semimetals, characterized by Weyl/Dirac nodes in the bulk and Fermi arcs on the surfaces, are new states of three-dimensional (3D) quantum matters, different from topological insulators. Weyl nodes are stable topological objects, and can be viewed as effective magnetic monopoles in the 3D momentum space. Its time-reversal invariant version ---- 3D Dirac node, however, consists of two copies of distinct Weyl nodes with opposite chirality, and requires additional symmetry protection, such as the crystal symmetry. Novel properties, such as negative magneto-resistance and non-local transport, can be expected for such semimetals, due to the presence of chiral anomaly. Recently, several Dirac semimetal (Na3Bi and Cd3As2) and Weyl semimetal (HgCr2Se4 and TaAs) compounds have been predicted and experimentally verified. In this talk, I will review the theoretical progress with focus on the predictive roles of first-principles calculations in this field. Some recent experimental progress will be also addressed. 

 

报告地点:国家同步辐射实验室二号楼报告厅

报告时间:2015年4月10日(周五) 9:00-10:00

参加人员:欢迎感兴趣的师生参加