报告摘要:Kagome compounds provide a fertile playground to explore the rich interplay between geometry, topology and electronic correlations. In this talk, we focus on a topological kagome metal CsV3Sb5 which exhibits cascade of symmetry-breaking electronic phases. Deeply in the CDW state, we found the emergence of electronic nematicity that intertwines with CDW and superconductivity, drawing strike parallel to the high temperature superconductors. A new CDW phase induced by pressure, evolving from the electronic nematicity in ambient-pressure triple-Q CDW state, is observed between Pc1 ~ 0.76 GPa and Pc2 ~ 2.02 GPa for the first time. Such new CDW, ascribed to a possible stripe-like CDW order with a unidirectional 4a0 modulation, is likely to intertwine with superconductivity and leads to the two-dome feature of the superconducting phase. We find that the superconducting gap is significantly enhanced between the two SC domes, and the temperature dependence of the SC gap in this pressure range severely deviates from the conventional BCS behavior, evidencing for strong Cooper pair phase fluctuations. At low temperatures, the topological surface states cooperate with superconductivity, and Majorana zero modes can be realized inside the vortex cores. All these results establish CsV3Sb5 as an ideal playground to study the topology and correlation driven exotic electronic orders.
陈仙辉,1992年在中国科学技术大学获博士学位。现为中国科学技术大学教授,中国科学院院士,发展中国家科学院院士。曾在德国卡尔斯鲁厄研究中心和斯图加特马普固体物理研究所做洪堡学者,先后在日本高等研究院(北陆)、美国休斯敦大学德克萨斯超导研究中心、新加坡国立大学做访问教授。1998年获国家杰出青年基金,2002年获聘教育部“长江学者”特聘教授。主要研究方向为超导、强关联和拓扑量子等新型功能材料的探索及其物理研究,已在《自然》(8篇)、《科学》(2篇)、《自然》子刊(24篇)和《物理评论快报》(41篇)等刊物接受、发表SCI论文460余篇。2008年获教育部和李嘉诚基金会―长江学者成就奖,2009年获中国物理学会―叶企孙奖,2009年获香港求是科技基金会―求是杰出科技成就集体奖,2013年获国家自然科学一等奖,2015年获国际超导材料Bernd T. Matthias奖, 2017年获首届全国创新争先奖章,以及何梁何利基金科学与技术进步奖,2019年获发展中国家科学院物质科学奖, 2020年获上海市自然科学一等奖等。
04
龚新高院士(复旦大学、广东以色列理工学院)
报告题目:From atoms to computer,and back 报告摘要:The rapid development of computer technology and of efficient algorithms has had a deep impact on science. The computation and simulation on the realistic condensed matter system become a practical experiment. The calculations provide precious insight, accurate prediction, and replace difficult experiment, also used to help build the present computers and in the future that will in turn be used to simulate even more complex phenomena. I will briefly review the development of so-called computational condensed matter physics, and shall illustrate the power of this approach with a number of examples. I will also comment what is the present challenges and possible avenues of future development.