Fermi-liquid effects are incorporated into the quasiclassical theory of superconductivity to give a quantitative theory for understanding tunneling experiments on real metals in high magnetic fields. The theory is formulated for arbitrary impurity scattering and anisotropy. Numerical calculations are done for the dirty, isotropic limit. The calculations for low spin-orbit scattering show that the energy difference in a magnetic field between spin-up and spin-down electrons is proportional to the l=0 antisymmetric Fermi-liquid parameter as confirmed by recent experiments. Furthermore, this same Fermi-liquid parameter is shown to renormalize the Pauli-limiting field in the calculation of the upper critical field. Recent experiments on thin films of Al are compared with the theoretical calculations.

• Received 18 June 1984

DOI:https://doi.org/10.1103/PhysRevB.31.5811