学术报告
题目: [栖湖讲座(第五十一期)] Topological Flat Bands in Stoichiometric Materials
时间: 2023年09月21日 10:00
地点: 怀柔园区X1南楼101会议室
报告人: 徐远锋

浙江大学  研究员

腾讯会议:826-641-036

会议密码:0921

会议链接:https://meeting.tencent.com/dm/qxErD1HjtZA1

报告摘要:

Flat bands in crystalline materials come in two kinds: atomically flat and topologically flat. Flat atomic bands are topologically trivial and commonly exist in layered materials and heavy fermion systems. Topological flat bands were recently discovered in twisted 2D materials, where the coexistence of nontrivial band topology and strong electronic correlation manifests kinds of exotic quantum phases, such as quantum anomalous Hall effect, magnetism, correlated insulating states, and superconductivity. In addition, a few 2D line-graph lattices with s orbitals were also proposed to have topological flat bands in the tight-binding approximation. Compared with the twisted superlattice, stoichiometric flat-band materials are much easier to synthesize and have a larger carrier density. Here I’ll introduce a general construction of flat bands in both 2D and 3D crystals. Using the magnetic topological quantum chemistry theory, we have a full classification of band topologies in paramagnetic and magnetic materials both with and without spin-orbit coupling. These advantages enable a complete understanding of flat-band features in most materials. By analyzing the geometry and symmetry properties, a high-throughput search and classification of topological flat-band materials were performed to build a material database.

报告人简介:

徐远锋,2019年博士毕业于中科院大地,2019-2022年先后在德国马普所微结构大地、美国普林斯顿大学物理系从事博士后研究。2022年12月加入浙江大学物理学院关联物质研究中心。主要从事凝聚态理论与材料计算研究。

邀 请 人:钱 天 研究员

联 系 人:王慧颖 why@iphy.ac.cn