Discovery of Topological Magnets in 2D and 3D and the New Frontiers

In this talk I present experimental realizations and properties of 2D and 3D topological magnets in novel Weyl, Dirac and Kagome materials building up on earlier results on topological insulators (Hasan & Kane, RMP 2010) but including recent results "A three-dimensional magnetic topological phase" (arXiv:1712.09992 (2017), Science 2019); "Topological quantum properties of chiral crystals" (Nature Materials (2018); "Topological Hopf and Chain Link Semimetal States" (Physical Review Letters 119, 156401 (2017)); "Magnetic Weyl fermion semimetals in the R-AlGe family of compounds" (Physical Review B (2018)); "Giant and anisotropic many-body spin–orbit tunability in a strongly correlated kagome magnet" (Nature 562, 91–95 (2018)), Chern magnets (Nature 2020, Nature Physics 2020) and "Unconventional chiral charge order (magnetic) in the normal state of kagome superconductor KV3Sb5" (Nature Materials 2021). I conclude by providing the new frontiers of research opened by the discovery of topological magnets (based on a recent review by Yin, Pan & Hasan <b>Nature Reviews Physics 3, 249–263 (2021))</b>