Superconductivity in the Metal Rich Li-Pd-B Ternary Boride

Superconductivity at about 8 K was observed in the metal-rich Li-Pd-B ternary system. Structural, microstructural, electrical, and magnetic investigations for various compositions proved that the Li2Pd3B compound, which has an antiperovskite cubic structure composed of distorted Pd6B octahedrons, is responsible for the superconductivity. This is the first observation of superconductivity in metal-rich ternary borides containing alkaline metal and Pd as a late transition metal. The compound prepared by arc melting has a high density and is relatively stable in the air. The upper critical fields H(c2)(0) estimated by linear extrapolation and the Werthamer-Helfand-Hohenberg theory are 6.2 and 4.8 T, respectively.