DHVA STUDIES OF A-15 SUPERCONDUCTORS AT H LESS-THAN-OR-EQUAL-TO 40-T

Better single crystals, together with the use of high magnetic fields, have recently resulted in direct dHvA measurements of parts of the Fermi surfaces of the high Tc superconductors Nb3Sn and V3Si. The results of high precision band structure calculations are now beginning to appear for these materials, so that direct comparisons of theory and experiment, for the electronic structure of at least some of the A-15 s, are now possible. The experimental data are reviewed in this paper in light of the available band structure results. Finally, the combined application of high precision quantum oscillation measurements and band structure calculations, to understand the structural transformation and defect behavior of A-15 materials, is briefly considered. © 1979.