Electronic Topology and Correlations in Kagome Metals

Explore the fascinating world of kagome metals in this 47-minute lecture by Riccardo Comin from the PCS Institute for Basic Science. Delve into the unique properties of the kagome lattice, a two-dimensional structure composed of corner-sharing triangles, and discover how it combines magnetism, spin-orbit coupling, and geometric frustration to create a promising platform for studying topology and strong correlations. Learn about the three key features of kagome electronic band structure: Dirac points, van Hove singularity, and flat bands. Examine experimental studies on various kagome compounds, focusing on transition metal stannides (Fe3Sn2, FeSn, and CoSn) and their manifestations of topological physics. Investigate the realization of the Kane-Mele model for 2D Dirac fermions and the discovery of flat bands with nontrivial topology. Explore recent findings on the AV3Sb5 family of correlated kagome metals, where superconductivity and charge-density-waves coexist, and understand the role of van Hove singularity in creating conditions for multiple Fermi surface instabilities and the emergence of collective electronic phases.