Pauli Limiting and the Possibility of Spin Fluctuations in the A15 Superconductors

From the critical-field data on the strongly Pauli limited superconductor V₃Ga it is shown that large electron-electron interactions (and their associated spin fluctuations) may play an important role in the superconductivity of the $A15$ superconductors. This possibility is shown to be consistent with existing Tc, heat-capacity, and spin-susceptibility data on several $A15$ superconductors.