Superconducting properties and μSR study of the noncentrosymmetric superconductor NbOs.

The properties of the noncentrosymmetric superconductor (α-[Formula: see text] structure) NbOs have been investigated using resistivity, magnetization, specific heat, and muon spin relaxation and rotation (μSR) measurements. These measurements suggest that NbOs is a weakly coupled ([Formula: see text]) type-II superconductor ([Formula: see text]), having a bulk superconducting transition temperature T   =  3.07 K. The specific heat data fits well with the single-gap BCS model indicating nodeless s-wave superconductivity in NbOs. The μSR measurements also confirm [Formula: see text]-wave superconductivity with the preserved time-reversal symmetry.