First-principles study on superconductive properties of compressive strain-engineered cryogenic superconducting heavy metal lead (Pb)

As one of the main materials in the practical application of superconductor, lead (Pb) has been used to manufacture superconducting AC power cable and some weak current fields. With the development of manufacturing technology, more and more researchers focus on exploring the physical and chemical properties of cryogenic superconducting materials, instead of blindly pursuing the improvement of the superconducting transition temperature (T _c). In this paper, the structural properties and superconducting transition temperature under high pressure of Pb have been studied by first-principles calculations. It has shown that Pb can withstand the compressive strain up to 10% while the lattice structure remains stable, indicated by the calculations of phonon band structures. From 0% to 10% compressive strain, there is neither a band-gap nor changing of the band structure. The changing of electronic DOS at the Fermi level leads to a decreasing of T _c. Our calculations show that Pb is a stable elemental metallic superconductor even under high pressure, which explains the reason why it has been used in practical productions. (paper)