From LaH(10) to room–temperature superconductors

Thermodynamic parameters of the LaH(10) superconductor were an object of our interest. LaH(10) is characterised by the highest experimentally observed value of the critical temperature: [Formula: see text] K (p(a) = 150 GPa) and [Formula: see text] K (p(b) = 190 GPa). It belongs to the group of superconductors with a strong electron-phonon coupling (λ(a) ~ 2.2 and λ(b) ~ 2.8). We calculated the thermodynamic parameters of this superconductor and found that the values of the order parameter, the thermodynamic critical field, and the specific heat differ significantly from the values predicted by the conventional BCS theory. Due to the specific structure of the Eliashberg function for the hydrogenated compounds, the qualitative analysis suggests that the superconductors of the La(δ)X(1−δ)H(10)-type (LaXH-type) structure, where X ∈ {Sc, Y}, would exhibit significantly higher critical temperature than T(C) obtained for LaH(10). In the case of LaScH we came to the following assessments: [Formula: see text] K and [Formula: see text] K, while the results for LaYH were: [Formula: see text] K and [Formula: see text] K.