Superconductivity and Band Structure from a Single Pseudopotential: Zinc and Cadmium

Abstract

Three values of the electron-phonon mass enhancement $\lambda$ for zinc and cadmium are compared: one obtained from the ratio of the electronic-specific-heat density of states and the band-structure value calculated from a pseudopotential approach, one calculated directly by means of the same pseudopotential, and one extracted by other authors from values of the superconducting transition temperature $T_c$ and the Debye temperature ⊖. For both metals the agreement between all three $\lambda$ values is very good, indicating the correctness and uniqueness of the pseudopotential. Calculations performed with other proposed pseudopotentials give very different values of $\lambda$.