Properties of the Superconducting State in YThH12 Compound at 60 GPa: Strong-Coupling Approach

Abstract

Hydrogen-rich ternary compounds have recently emerged as potential candidates for high-temperature superconductors that do not require extremely high pressure conditions. In this work, we provide a quantitative investigation of the thermodynamic properties of the superconducting state in the YThH₁₂ compound at a pressure of 60 GPa. Using the Migdal–Eliashberg formalism, we show that the critical temperature of this material is high (T_C = 200.29 K), assuming a Coulomb pseudopotential value of 0.1. In addition, the theoretical framework employed allows for the determination of other key thermodynamic quantities, including the superconducting energy gap, free energy, specific heat, and critical magnetic field. The thermodynamic relationships associated with these parameters differ from those predicted by the Bardeen–Cooper–Schrieffer theory. Our findings indicate that strong-coupling and retardation effects are critical to the superconducting state in this compound, making it inconsistent with a weak-coupling description.