Fluxoid quantum number at Hc3

Abstract

For a cylinder in an axial magnetic field the laigest field at which superconductivity nucleates is the same as the surface nucleation field of the semi-infinite half-space when the radius R of the cylinder is much laiger than the temperature-depen dent coherence length ε. From the solution of the multiply connected surface sheath one obtains the number of fluxoid quanta which are locked-in at the nucleation field as a function of R/ε.