The de Haas-van Alphen effect in Sb(Sn) and Sb(Te) alloys

Abstract

Measurements have been made of the de Haas-van Alphen effect in Sb(Sn ) alloys containing up to 0.58 at % Sn and Sb(Te) alloys with up to 0.26 at % Te. The maximum electron period in the bisectrix-trigonal plane increased from 14.66 • 10 -7 G -1 in pure Sb to 68.0 x 10 -7 G-r in the most concentrated Sn-doped sample, whereas the maximum hole period decreased from 16.33• -7 to 7.4x 10 -7 G -1. The Te doping had the opposite effect--increasing the number of electrons and decreasing the number of holes. The results of measurements of effective mass and Fermi surface area are found to be consistent with a rigid-band model of these dilute alloys. Both electron and hole bands are strongly nonparabolic and a two-band model is used to estimate that the gap below the electron pocket at L is 110 • 25 me V. The Fermi levels of electrons and holes in Sb are estimated to be 150+ 10 and 180 + 40 me V, respectively, It is predicted that the electron pockets will be completely emptied for an alloy with O. 78 + O.07 at % Sn. Pseudopotential calculations suggest that the rigid-band model is a reasonable approximation in these dilute alloys.