Ranges and limits of the electron-phonon coupling constant of superconductivity

Abstract

A simplified study of the effect of including self energy and vertex corrections to the BCS critical temperature Tc expression is carried out her to identify the possible ranges and limits of the electron-phonon coupling constant λ in superconductivity. The results show that the inclusion of the self energy will reduce the BCS Tc to that of McMillan which is generally believed to yield unrealistic λ while the inclusion of vertex corrections produce a Tc that provides the realistic ranges and limits of λ in superconductivity. The implication of these results is then discussed.

Nigerian Journal of Physics Vol. 16(2) 2004: 162-166