学术报告（6.13）

主持人：姚道新副院长

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 first outline the generic challenge of the many-body problems in condensed matter physics to the non-experts.  It will then 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.

Reference: http://www.physics.sjtu.edu.cn/guwei

报告人简介：顾威，国家海外高层次人才项目教授，上海交通大学物理与天文系。1991年获得台湾淡江大学学士学位。2000年获得美国田纳西大学（Knoxville）博士学位。2001-2003年在美国University of California Davis做博士后研究。2003年起在美国Brookhaven National Laborator & Stony Brook University工作。2015年开始在上海交通大学物理与天文系工作。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重要的贡献，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。