Abstract
Kagome metals are compelling materials platforms for hosting electronic states that feature an interplay between topologically nontrivial electronic states and correlated electron phenomena. These two features can, for instance, arise from the Dirac points, flatbands, and saddle-points endemic to the band structures of kagome networks. States featuring orbital magnetism and unconventional superconductivity are predicted to arise at select fillings, in particular within systems where the saddle-points are located close to the Fermi level. In this talk I will present some of our recent work exploring the electronic properties of two new classes of kagome metals, each with Z2 topology and saddle points close to Fermi energy. Specifically, our work studying the compounds AV3Sb5 (A=K, Cs, Rb) and RV6Sn6 (R=rare earth ion) will be presented. The former family of compounds exhibit an unusual charge density that shows hints of time-reversal symmetry breaking intertwined with a low temperature superconducting ground state. The latter family provide a tunable platform for interfacing magnetic order and frustrated magnetic interactions with a topologically nontrivial kagome band structure. Unconventional electronic properties observed in each class of these new kagome compounds and open questions will be discussed.
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