YRu${}_3$B${}_2$ -- a kagome lattice superconductor

Abstract

We report the synthesis and physical properties of a polycrystalline, hexagonal boride YRu${}_3$B${}_2$. Our resistivity and heat capacity measurements indicate that YRu${}_3$B${}_2$ is a weakly coupled superconductor, with critical temperature $T_c$ = 0.63 K and upper critical field ${\mu }_0{H}_{c2}$ (0)=0.11 T. Density functional theory calculations, together with chemical-bonding analysis, reveal that the electronic states at and near the Fermi energy level are dominated by the Ru kagome sublattice.