Heat capacity of type-I superconductivity in the Dirac semimetal PdTe2

Type-I superconductivity was recently reported for the Dirac semimetal PdTe2 (Tc ≈ 1.6 K) with, remarkably, multiple critical fields and a complex phase diagram. Here, measurements of the specific heat utilizing a thermal relaxation technique are presented. Conventional weak-coupling BCS superconductivity is confirmed by examining the temperature dependence of the specific heat in zero field. By probing the latent heat accompanying the superconducting transition, thermodynamic evidence for type-I superconductivity is attained. The presence of the intermediate state is observed as a significant broadening of the superconducting transition onto lower temperatures at high fields as well as irreversibility in the specific heat in zero-field-cooled data at 8.5 mT