Superconducting and semiconducting properties of electron-beam evaporated materials. Final technical report, December 1, 1975-October 31, 1983

The objective of this program was to undertake a comprehensive study of the upper critical field Hc2 of the high-T/sub c/ A15 superconducting compounds. Interest in this problem was occasioned by the availability of new materials preparatory techniques (electron beam coevaporation) that made possible for the first time the preparation of samples in which the relevant material parameters (e.g., composition and order) could be systematically varied. The work involved critical tests of the existing theory, extension of the theory, use of the theory to determine important microscopic material parameters, and development of new principles for the optimization of Hc2 in practical high-field superconducting conductors. As a result of this program, optimization of the practically important high-field superconductors Nb3Sn and V3Ga are proceeding more rationally, fundamental additions to the theory of high-field superconductors have been introduced, and new insights have been obtained regarding the factors governing the high T/sub c/'s of this important class of superconductors