Investigating the superconducting and magnetic properties of two new superconducting ternary osmium silicides: NbOsSi and TaOsSi

Recently, Eckert and co-authors synthesised osmium based two superconductors, NbOsSi and TaOsSi, and found that these compounds exhibit superconductivity below a transition temperature of 3.5K and 5.5K, respectively. We have performed a quick Xpress muSR measurements and found time-reversal symmetry breaking fields in TaOsSi. We now propose to study the magnetic and superconducting properties of NbOsSi and TaOsSi, by a combination of zero-field and transverse-field muSR measurements. We plan to investigate how the symmetry of the superconducting gap structures varies between the Ta- and Nb-compound and confirm if spontaneous TRS breaking fields arises in the superconducting state of both materials and hence establish these superconductors as a new family of TRS breaking superconductors.