Characterization of Nb3Sn diffusion layer material

An analysis is given of the fundamental limitations of different techniques for characterizing the superconducting properties of A15 compound layers prepared by solid state diffusion From a bronze matrix. Theoretical and experimental results are presented for inductive measuremenns of the local variation of the critical temperature, Tc, together with preliminary specific heat measurements. Finally a discussion is given of the problem of making similar measurements for the critical current, Jc, and upper critical field, Bc2.