Superconducting properties of the ternary transition-metal silicide Zr2Ru3Si4

摘要

Superconducting properties of the polycrystalline Zr2Ru3Si4 were investigatedby the electrical resistivity, magnetization and specific heat. By thesemeasurements, bulk superconductivity with transition temperature Tc = 5.5 K wasconfirmed. Moreover, Zr2Ru3Si4 was found to be a type-II andintermediate-coupling superconductor. Interestingly, the electronic specificheat shows a deviation from a one-gap s-wave model and Hc2(T) shows unusualpositive curvature in the vicinity of Tc. The first principle's calculationshows the existence of plural anisotropic Fermi surfaces. These results suggestthat Zr2Ru3Si4 is not an isotropic single-gap superconductor, but possibly amulti-gap or an anisotropic gap superconductor.