Topological flat bands in frustrated kagome lattice CoSn

Electronic flat bands in momentum space, arising from strong localization of electrons in real space, are an ideal stage to realize strong correlation phenomena. In certain lattices with built-in geometrical frustration, electronic confinement and flat bands can naturally arise from the destructive interference of electronic hopping pathways. Such lattice-borne flat bands are often endowed with nontrivial topology if combined with spin-orbit...