Normal Inclusions in Type II Superconductors

A modified local model of an isolated fluxline has been used to calculate the energy of a system of fluxlines and a magnetically reversible cylindrical normal inclusion. Strict attention to quantisation of fluxoid leads to forces which are comparable to those derived from simple considerations of condensation energy; they can extend to distances much greater than the coherence length. It is found that an analytical treatment of the same problem by Mkrtchyan and Shmidt, when generalised, can give the energy of the system to better than 10% in most circumstances.