重费米子材料新奇拓扑态、微波光子学、轨道活性蜂窝材料、量子材料中的相互作用 | 本周直播物理讲座

报告人：Dr. Lin Jiao, National High Magnetic Field lab

时间：8月4日（周二）10:00

单位：中科院物理所

参加方式：讲座以线上形式进行，采用“腾讯会议”软件

会议ID：978 571 723     

会议密码：0804

直播链接： 

https://meeting.tencent.com/l/sPaAERFx9LH1

摘要：

In this talk, I will focus on my recent work on two prototype heavy fermion materials SmB6 and UTe2. SmB6 is a Kondo insulator while UTe2 is a ferromagnetic superconductor, both are extremely rare examples of their categories. Using scanning tunneling microscopy at very low temperature, we demonstrate the peculiar topological surface states on symmetry-broken boundaries. By comparatively discussing these two materials, I would like to demonstrate how the strong electronic correlations can tailor the surface properties of heavy fermions in atomic scale. As a result, these materials can provide platforms to realize novel topological quantum states, such as "heavy" Dirac electrons in SmB6 and "chiral" Majorana fermions in UTe2, which could lead potential applications in the field of quantum science and technology.

报告人简介：

Dr. Lin Jiao obtained his Ph.D in Condensed Matter Physics in 2014 at Zhejiang University under the supervision of Prof. Huiqiu Yuan. After graduation, he spent four years at Max Planck Institute for Chemical Physics of Solids, being partially sponsored by the Alexander von Humboldt fellowship. In 2018, he moved to University of Illinois at Urbana Champaign as a Postdoctoral research associate. Recently, he joined the National High Magnetic Field lab as a research faculty member. His major research interests lie in studying: emergent behavior and critical fluctuations in the realm of strongly correlated materials (especially heavy fermions), symmetry protected massless fermions in topological material, and pairing symmetry of unconventional superconductors. Currently, he is focusing on combining transport and microscopic spectroscopy measurements in extreme conditions, including ultra-low temperatures and very high magnetic fields.

单位：Frontiers of Physics编辑部，高教社自然科技期刊中心

参会方式：蔻享直播

直播链接：https://www.koushare.com/live/liveroom?islive=0&lid=334&roomid=038932

摘要：

Based on the symmetry principle, we provide a unified view on a class of orbital-active honeycomb materials. They possess a pair of degenerate orbitals on each site forming the 2D(E-)  representation of the D₃ , or,  C_3v point group symmetry.  We found the same principle applies to a variety of solid state systems including the p_x and p_y orbitals of bismuthene, stanene, the exciton-polariton lattice, and the d_x2-y2 and d_r2-3z2 -orbitals in transition-metal oxide layers, and also the ultra-cold atom optical lattices. I will explain that the recent focus of the twisted bilayer graphene is a particular example to manifest this symmetry. Such a unified view brings a variety of interesting properties, including the strong correlation physics of Wigner crystallization and ferromagnetism inside flat bands, interaction induced spontaneous quantum anomalous Hall states, and the orbital-assisted f-wave superconductivity. We also propose a new mechanism to boost the topological gap to the full scale of atomic spin-orbit coupling, which can reach the order of 1eV and has been recently realized in bismuthene on the substrate of SiC. In the Mott-insulating states, the orbital exchange is heavily frustrated as described by a novel quantum 120^⁰ -model -- a cousin of the Kitaev model, whose classic ground state problem maps to the fully packed loop model in the honeycomb lattice. The “order from disorder” study is performed to analyze its quantum ground state ordering. 

报告人简介：

Congjun Wu received his Ph.D. in physics from Stanford University in 2005, and did his postdoctoral research at the Kavli Institute for Theoretical Physics, University of California, Santa Barbara, from 2005 to 2007. He became an Assistant Professor in the Department of Physics at the University of California, San Diego (UCSD) in 2007, an Associate Professor of Physics at UCSD in 2011, and a Professor of Physics at UCSD in 2017. He was elected to be a Fellow of American Physical Society in 2018. His research interests are exploring new states of matter and reveling their organizing principles, including quantum magnetism, superconductivity, topological states, mathematical physics, and the numerical method of quantum Monte Carlo simulations.

单位：中科院强耦合量子材料物理重点实验室、中国科大物理系、中国科大科研部

参会方式：蔻享直播

直播链接：https://www.koushare.com/live/liveroom?islive=0&lid=327&roomid=616985

报告人简介：

何俊峰，中国科学技术大学特任教授, 博士生导师。2013年在中科院物理所获得凝聚态物理博士学位，2013-2015年在波士顿学院从事博士后研究，2015-2018年在斯坦福大学从事博士后研究。2018年担任日本广岛大学客座教授。主要从事量子材料的电子结构研究，在包括Nature，Science，Nature Materials，Science Advances，PRL，PNAS，Nature Communications等国际重要学术期刊上发表论文40余篇。

单位：檀时钠教授（北京大学）、Frontiers of Physics编辑部

参会方式：蔻享直播

直播链接：https://www.koushare.com/live/liveroom?islive=0&lid=337&roomid=558125

报告人简介：

戴瑾，毕业于北京大学物理系，通过CUSPEA项目赴美留学，获德克萨斯大学高能物理学博士学位，从事过多年的基础物理学研究工作。攻读博士期间，加入了诺贝尔奖获得者温伯格的研究小组，师从2017年基础物理学突破奖获得者Polchinski，共同发明了弦论中的D膜理论。论文被引用超过千次。
后转向无线通讯/IT产业，曾在美国高通公司工作。现任上海一家半导体公司高管，提交过150多项发明专利。业余时间做科普，著有《从零开始读懂量子力学》。

更多报告信息：中国物理学会期刊网学术讲座列表