EFFECT OF HYDROSTATIC-PRESSURE ON THE FERMI-SURFACE OF WHITE TIN

The derivatives with respect to hydrostatic pressure of 12 extremal cross-sectional areas of the Fermi surface of tetragonal white ( beta ) tin have been measured by the fluid helium de Haas van Alphen phase shift technique. The samples were carefully aligned in situ to have a crystal symmetry axis ( left bracket 001 right bracket , left bracket 100 right bracket , or left bracket 110 right bracket ) parallel to the magnetic field. The measured derivatives differ significantly from most values found previously by both direct and indirect methods; it is believed that the present work provided the first reliable comprehensive determination of these quantities. The present experiments also confirm the conclusions of magnetostriction experiments that there is a second orbit normal to left bracket 100 right bracket on the sixth zone surface not identified in earlier conventional de Haas van Alphen work, and that the third zone extremal areas normal to left bracket 001 right bracket are larger than previously accepted values determined in de Haas van Alphen studies.