Superconductivity in the ternary silicide TrIrSi (Tr = Ti, Zr, and Hf)

Abstract

We discover a new superconductor, TiIrSi at Tc = 1.4 K, and reveal a superconducting state of TrIrSi (Tr = Ti, Zr, and Hf) by using dc magnetic susceptibility , electrical resistivity , and specific heat C(T) measurements. Superconductivity of TrIrSi is confirmed in at Tc = 1.4, 1.85, and 3.4 K, respectively. The electronic specific heat of TrIrSi can be fitted with the theoretical BCS curve of the weak-coupling limit with /= 1.43. Measurements in several magnetic fields suggest that TrIrSi is a type-II superconducting material with upper critical fields of (0) = 0.751, 0.618, and 2.23 T, respectively. The electron–phonon coupling constants are calculated to be 0.441, 0.464, and 0.545, which are consistent with the weak-coupling limit inferred from the specific jump. The Tc of TrIrSi depends on and is inversely proportional to .