Valence-Band Structure of PtSb2

The low-temperature galvanomagnetic properties of $p$-type Pt${\mathrm{Sb}}_2$ are reported for magnetic fields up to 60 kG, using samples with extrinsic current-carrier densities from 6 × ${10}^{16}$ to 1.5 × ${10}^{19}$ ${\mathrm{cm}}^{-3\mathrm{}}$. From the low-field properties and the Shubnikov—de Haas oscillations it is found that the valence-band maxima are six ellipsoids on $〈100〉$ axes, the principal inertial effective masses being in the ratio 0.61:1:1.64, the least cyclotron mass $(0.168\mathrm{}\pm 0.005)m$, and scattering close to isotropic. The band parameters are found to be independent of the energy of the current carrier, suggesting a direct band gap greater than 0.4 eV; cf. indirect band gap of about 0.1 eV. The ratio of effective masses was obtained by analyzing small beats in the amplitude of the oscillations in the resistivity.