摘要

Recent discovery of iron-based high temperature superconductors has generated intense research activities in the fields of condensed matter physics, materials sciences and physical chemistry.  While only very limited solid understandings have been obtained and more puzzles are being unveiled, it has become clear that this new class of materials is a perfect host for the complex and rich condensed matter physics involving multiple physical effects with similar energy scales.
This talk will address the electronic and magnetic structure of the iron based superconductors, focusing on effects of the symmetries (and their violations) in the spin, charge, orbital and the translation degree of freedoms.  First, the magnetic structure will be discussed in connection with a hidden ferro-orbital order.  Second, the rich variety of magnetic orders found in the families of the parent compounds will be explained using a simple unified picture.  Third, the observed strong suppression of the ordered magnetic moment from the large local moment will be addressed, demonstrating the subtle roles of itinerant carriers.  Finally, novel physical effects of disorder will be discussed in a few case studies.
Referencees
[1]  Chi-Cheng Lee, Wei-Guo Yin, and Wei Ku, Phys. Rev. Lett. 103, 267001 (2009).
[2]  Wei-Guo Yin, Chi-Cheng Lee, and Wei Ku, Phys. Rev. Lett. 105, 107004 (2010).
[3]  Yu-Ting Tam, Dao-Xin Yao and Wei Ku, Phys. Rev. Lett. 115, 117001 (2015).
[4]  Tom Berlijn, Chai-Hui Lin, William Garber and Wei Ku, Phys. Rev. Lett. 108, 207003 (2012).
[5]  Tom Berlijn, P. J. Hirschfeld, and Wei Ku, Phys. Rev. Lett. 109, 147003 (2012).
[6]  Limin Wang, et al., Phys. Rev. Lett. 110, 037001 (2013).
[7]  Chia-Hui Lin, et al., Phys. Rev. Lett. 107, 257001 (2011).
 

报告人简介

顾威教授1991年毕业于台湾淡江大学物理学系，获理学学士学位。2000年于美国田纳西大学物理系，获博士学位。2001-2003年在美国加州大学戴维斯分校博士后工作。2003年受聘为美国布鲁克海文国家实验室研究员并担任美国石溪大学物理系兼任教授。他的主要研究领域为凝聚态理论和量子材料计算，在铁基超导体，电子激发，第一性原理多体计算方法等方向有国际上广为人知的贡献，发表论文70 余篇，其中PNAS 1 篇，Nature Physics 1 篇，Phys. Rev. X 1篇，Phys.Rev.Lett. 30余篇。
 

研究方向：

1.关联电子材料及其激发

2.无序杂质在材料中的物理效应

3.高温超导之非传统理论

4.拓扑绝缘体之解析结构

5.量子多体计算及方法