Superconductivity in the Tin-Gallium System

Abstract

Superconducting transition temperatures have been measured for a number of Sn-Ga compositions in both the "quenched" (quick cast) and annealed states. The increases in $T_c$ in the "quenched" samples are not large (usually about 0.1-0.2°K), and can be accounted for on the basis of internal stresses in the sample. The equilibrium transition temperatures are consistent with the known phase diagram of Predel. Within the Sn solid solution $T_c$ first drops (mean-free-path effect), then rises to 3.9°K. Compositions in the neighborhood of the eutectic show depressed and broadened transitions; these are attributed to proximity effects.