2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/174694A density-functional formalism for superconductivity {\em and} magnetism is presented. The resulting relations unify previously derived Kohn-Sham equations for superconductors and for non-collinear magnetism. The formalism, which discriminates Cooper pair singlets from triplets, is applied to two quantum liquids coupled by tunneling through a barrier. An exact expression is derived, relating the eigenstates and eigenvalues of the Kohn-Sham equations, unperturbed by tunneling, on one side of the barrier to the proximity-induced ordering potential on the other.Phys. Rev. B, accepted (2008)Materials ScienceSuperconductivitytext