Influence of the Vertex Corrections to the Electron-Phonon Interaction on the Value of the Critical Temperature of YH10

M. Kostrzewa Quantum Optics and Engineering Division, Institute of Physics, University of Zielona G?ra, Prof. Z. Szafrana 4a, 65-516 Zielona G?ra, Poland

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Theoretical studies available in the literature suggest that the compound YH10 is a promising candidate for a high-temperature superconductor with a phase transition temperature TC close to room temperature. Numerical solutions of the classical Eliashberg equations at 250 GPa led to the critical temperature of about TC=326 K. As expected, YH10 belongs to the group of superconductors with strong electron-phonon coupling, similar to others with TC above 200 K, for example, H3S, LaH10, or YH6. In 2018, a series of experiments were conducted, and the experimental verifications confirming the existence of a high-temperature superconducting state in LaH10 turned out to be groundbreaking. At the time, it seemed that such confirmation concerning YH10 would come very quickly. Unfortunately, so far there have been no successful experimental measurements on the high-temperature YH10 superconducting phase. The aim of this work is to show the effect of the vertex corrections to the electron-phonon interaction on the value of the critical temperature of YH10 at 250 GPa. Thus, it was shown that by including more complex equations into the calculations (the formalism of Eliashberg equations with the vertex corrections), the estimated value of the metal-superconductor phase transition temperature lowers significantly to TC=245.75 K. Furthermore, we point out that the influence of temperature on the effective electron mass exhibits a similar tendency as that concerning the LaH10 superconductor we studied earlier.

DOI:10.12693/APhysPolA.142.149 topics: YH10, high-temperature superconducting state, vertex corrections