Superconductivity in Tin-Bismuth and Tin-Antimony Alloys

The Meissner effect in a series of spherically shaped solid solution alloys of tin with bismuth and antimony has been investigated. Magnetization curves have been obtained as a function of temperature and composition, from which critical field curves and transition temperatures have been derived. Increasing breadth of the magnetization curves and frozen in moment have been observed with increasing solute concentration. Thermodynamic analysis of the critical field data has shown an interesting variation of the electronic specific heat coefficient $\gamma$ with solute concentration, which has been interpreted in terms of the overlapping band structure of tin.