Effect of Hydrostatic Pressure on Superconductivity of Pb

Abstract

The effect of hydrostatic pressure on superconductivity of face-centered cubic bulk Pb has been investigated by using first-principle calculations. The calculations were performed based on the density functional theory as implemented in Quantum ESPRESSO computational package. The electronic density of states (DOS), phonon density of states (PhDOS), isotropic Eliashberg function (α2F(ω)), electron-phonon coupling strength (λ), logarithmic phonon frequency ( log), and superconducting critical temperature (Tc) have been calculated within the general framework of Eliashberg formalism. The critical temperature was calculated using the modified McMillan formula. At equilibrium, where the hydrostatic pressure of the system is almost zero, the calculated Tc value is 7.86 K. It is relatively nearer to the experimental value of 7.2 K. The slight overestimation is attributed to DFT approximations used. Our calculations indicated that hydrostatic pressure suppresses superconducticvity of bulk Pb. It has been observed that Tc decreases from 7.86 K at equilibrium structure to almost zero at a pressure of 3500 kbar.