Exciton enhancement of the superconducting transition temperature in a metal-semiconductor system with spherical interface

A metal-semiconductor system with spherical interface has been studied to look for possible enhancement of the superconducting transition temperature, via the exciton-exchange mechanism. The calculated values are larger than the corresponding results for a plane interface, but still insufficient to account for recent experimental observations of Ghosh and Douglass on the Nb${\mathrm{Ge}}_2$-Ge system.