The characterization of high-pressure superconducting state in image compound: The strong-coupling description Original Research Article

The thermodynamic parameters of the superconducting state in Si2H6Si2H6 compound under the pressure at 275 GPa have been calculated. In the framework of the Eliashberg formalism, it has been shown that the critical temperature can reach extremely high values: TC(μ⋆)∈〈173.36,99.99〉TC(μ⋆)∈〈173.36,99.99〉 K, where the Coulomb pseudopotential (μ⋆)(μ⋆) belongs to the range from 0.1 to 0.3. The ratios RΔ≡2Δ(0)/kBTCRΔ≡2Δ(0)/kBTC and RC≡ΔC(TC)/CN(TC)RC≡ΔC(TC)/CN(TC) significantly exceed the values predicted by the BCS theory: RΔ(μ⋆)∈〈4.40,4.04〉RΔ(μ⋆)∈〈4.40,4.04〉 and RC(μ⋆)∈〈2.45,2.28〉RC(μ⋆)∈〈2.45,2.28〉. In contrast, View the MathML sourceRH≡TCCN(TC)/HC2(0) is smaller than in the BCS model: RH(μ⋆)∈〈0.137,0.149〉RH(μ⋆)∈〈0.137,0.149〉. Additionally, it has been stated that in the whole range of the existence of the superconducting state, the electron effective mass (View the MathML sourceme⋆) is large; View the MathML source[me⋆]T=TCmax=2.397me, where the symbol me denotes the electron band mass.