Superconductivity in a low carrier density system: A single crystal study of cubic Y3Ru4Ge13

Abstract

We have successfully grown the single crystal of Y3Ru4Ge13 which crystallizes in the cubic crystal structure with the space group Pm3n. Y3Ru4Ge13 exhibits superconductivity below 2.85K as determined using electrical resistivity, magnetic susceptibility and heat capacity measurements. Hall Effect measurements show that the Hall coefficient RH is negative and its value decreases rapidly with temperature, which is highly unusual. The simple estimation of the carrier concentration gives a value ≅1020/cm3, which are 2–3 orders of magnitude lower than that of a conventional metal like Cu, suggesting Y3Ru4Ge13 is a semimetal.