Superconductivity in the ${\mathbb{Z}}_2$ kagome metal KV${}_3$Sb${}_5$

Abstract

Here we report the observation of bulk superconductivity in single crystals of the two-dimensional kagome metal KV${}_3$Sb${}_5$. Magnetic susceptibility, resistivity, and heat capacity measurements reveal superconductivity below $T_c=0.93$K, and density functional theory (DFT) calculations further characterize the normal state as a ${\mathbb{Z}}_2$ topological metal. Our results demonstrate that the recent observation of superconductivity within the related kagome metal CsV${}_3$Sb${}_5$ is likely a common feature across the AV${}_3$Sb${}_5$ (A: K, Rb, Cs) family of compounds and establish them as a rich arena for studying the interplay between bulk superconductivity, topological surface states, and likely electronic density wave order in an exfoliable kagome lattice.