Low-Temperature Thermodynamic Properties of Superconducting Antiperovskite CdCNi $$_3$$ 3

Abstract

We investigate the thermodynamic parameters of the superconducting antiperovskite CdCNi 3 using the Eliashberg approach which is an excellent tool to the exact characterization of the conventional superconductors. In particular, we reproduce the measured superconducting transition temperature (T C = 3.2 K) for a high value of the Coulomb pseudopotential (μ C = 0.22). Then we determine the energy gap, the thermodynamic critical field and the specific heat for the superconducting and normal state. On this basis, we show that the thermodynamic properties of CdCNi 3 differ slightly from the prediction of the Bardeen-Cooper-Schrieffer theory, which means that CdCNi 3 is a medium-coupling superconductor in contrast to related strongcoupling MgCNi 3 .

Properties of the Superconducting State in Hexagonal BaSn5

“…The Eliashberg equations have been solved for 2201 Matsubara frequencies (M = 1100) by using the method presented in [10] and [11] and recently tested in [12]. In the considered case, the obtained Eliashberg solutions are stable for T ≥ 0.6 K.…”