Properties of the superconducting state in compressed Sulphur

TL;DR

This study investigates the thermodynamic properties of superconducting sulfur under high pressure, revealing key parameters like critical temperature, Coulomb pseudopotential, and electron mass enhancement, using theoretical calculations.

Contribution

It provides detailed theoretical analysis of sulfur's superconducting state at 160 GPa, including critical parameters and ratios, using the Eliashberg formalism and modified formulas.

Findings

Critical temperature T_C = 17 K at 160 GPa

Critical Coulomb pseudopotential is 0.127

Electron effective mass ratio peaks at 1.77

Abstract

The thermodynamic properties of the superconducting state in Sulphur under the pressure at 160 GPa were determined. It has been shown that: (i) the critical value of the Coulomb pseudopotential is equal to 0.127; (ii) the critical temperature (T_{C} =17 K) should be calculated by using the modified Allen-Dynes formula; (iii) the effective electron-electron interaction is attractive in the range of frequencies from zero to the frequency slightly lesser than the maximum phonon frequency (~ 0.85\Omega_{max}); (iv) the dimensionless ratios 2\Delta (0)/k_{B}T_{C}, $\Delta C(T_{C})/C^{N}(T_{C}) and T_{C}C^{N}(T_{C})/H^{2}_{C}(0) are equal to 3.7, 1.65 and 0.16 respectively; (v) the ratio of the effective to bare electron mass reaches maximum of 1.77 for T=T_{C}.