An electron tunneling investigation of quench-condensed superconductors

Abstract

An electron tunneling investigation has been carried out on quench-condensed Bi, Ga, Pb, Pb∙75Bi∙25, Pb∙50Bi∙50, and Pb∙25Bi∙75. The energy gap and transition temperature have been measured for each sample. The tunneling derivative data have been analyzed in terms of the strong-coupling theory of superconductivity by means of a computer program of W. L. McMillan. The effective phonon spectrum, the Coulomb pseudopotential, the complex energy gap function, the pairing self-energy function, and the electron renormalization function have been determined for each sample. Certain parameters based on integrals over the phonon spectrum have also been calculated for each sample.