Surface superconductivity andH c3 in UPt3

Abstract

Surface superconductivity is studied within Ginzburg-Landau theory for two classes of models for the order parameter of UPt 3 . The first class assumes two independent one-dimensional order parameters (AB models), while the second assumes a single two-dimensional order parameter (E models). H c3 is calculated for all cases where the surface normal and magnetic field lie along high symmetry directions. Assuming specular reflection, it is found that except when H ĉ, the ratio H c3 /H c2 is either unity or equals its 'swave' value 1.695, although the precise H c3 vs. T curve predicted by the AB and E models differs for various geometries. The results are compared with recent experiments, and predictions are made for future experiments.