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De-Haas-van Alphen (DHVA) frequencies corresponding to the neck orbits of a majority-spin Fermi surface have been observed over a wide range of orientations in the ferromagnetic FCC alloy Co0.92Fe0.08. Self-consistent band-structure calculations can largely explain the experimental results, albeit that the predicted neck diameter is 20% too small.

A sample of YBa 2 Cu 3 O 7 was constructed by stacking a number of small single crystals. Magnetization measurements were made in magnetic fields up to 38 T, both parallel to the c -axis and to the basal plane. At 1.4, 4.2 and 20.4 K, a large irreversible magnetization was observed. The significance of these results for the superconducting properties is discussed.

The magnetization of high- T c superconducting REBa 2 Cu 3 O 7 compounds, where RE is Y or one of the rare-earth elements Eu, Gd, Dy, Ho, Er or Yb, has been measured in fields up to 29 T. Though the precise analysis of the data is hampered by the incomplete penetration of the magnetic field due to the shielding-current effect of the superconductivity, the magnetism associated with the rare-earth ions can reasonably be interpreted by crystal-field effects. All of the samples investigated were confirmed to be superconducting at 4.2 K in fields as high as 29 T.

de Haas-van Alphen frequencies in the (100) and (110) planes of Nb3Sn have been measured with a typical accuracy of 1%. Several frequency branches have been found between 100 and 1000 T. Effective masses corresponding to some of the orbits at symmetry directions have been estimated from the experiments. A pronounced anisotropy ( approximately 10%) in the upper critical field was observed. The magnitude of the critical field was found to be sample dependent. The DHVA data are interpreted using self-consistent new ASW band-structure calculations which include tetragonal distortion of the unit cell.

de Haas-van Alphen (dHvA) oscillations have been observed in ${\mathrm{Nb}}_{3}$Sn in the (110) plane and in ${\mathrm{V}}_{3}$Si at two orientations using single crystals of high resistance ratio and magnetic fields in excess of ${H}_{c2}$. The dHvA frequency data for ${\mathrm{Nb}}_{3}$Sn can be interpreted as a series of nested ellipsoids centered at $M$, as suggested by a recent high-precision calculation of the ${\mathrm{Nb}}_{3}$Sn Fermi surface.

The non-linear part of the magnetisation of pure Pd and dilute PdNi alloys (up to 0.56 at.% Ni) was measured in semi-continuous fields up to 35 T. The Ni-doped Pd shows a negative curvature at high fields whilst for pure Pd a small positive curvature was found as in previous measurements. In the alloys the curvature becomes more pronounced for higher Ni concentrations. These effects and their relation to recent DHVA measurements are discussed in this article.

De Haas-van Alphen oscillations have been observed in the magnetization of a power sample of ln3 Yb and are ascribed to a small spherical part of the Fermi surface.