Superconductivity of ternary silicide with the AlB2-type structure Sr(Ga0.37, Si0.63)2 -: art. no. 077003

A ternary silicide Sr(Ga-0.37, Si-0.63)(2) was synthesized by a floating zone method. Electron diffraction and powder x-ray diffraction measurements indicate that the silicide has the AlB2-type structure with the lattice constants of a = 4.1427(6) Angstrom and c = 4.7998(9) Angstrom, where Si and Ga atoms are arranged in a chemically disordered honeycomb lattice and Sr atoms are inercalated between them. The silicide is isostructural with the high-temperature superconductor MgB2 reported recently. Electrical resistivity and dc magnetization measurements revealed that it is a type-II superconductor with onset temperature of 3.5 K.