Superconducting properties of In doped ZrNi2Ga1−xInx

We report on the effect of In doping on the superconducting properties of ZrNi2Ga1−xInx (x = 0.0.05, 0.10, 0.15) Heusler alloys. While the samples with x < 0.1 exhibited the single phase, cubic L21 structure, small concentrations of ZrGa2-type orthorhombic secondary phases formed on the samples with x ≥ 0.1. Electrical resistivity and dc magnetization measurements showed that the superconducting transition temperature of the compounds decreased with increasing In concentration. All samples showed paramagnetic ordering above their respective superconducting transition temperature. The observations suggest that for x ∼0.45 the ZrNi2Ga1−xInx compound might exhibit a quantum phase transition.