Oscillatory Magnetoresistance in Mercuric Selenide

The oscillatory magnetoresistance (Shubnikov-de Haas effect) in oriented single crystals of mercuric selenide was measured at 1. 2 and 4. 2^ and in transverse magnetic fields up to 25 kG. Analysis of the periods of the oscillations for the magnetic field aligned with 〈110〉, 〈111〉, and 〈100〉 crystallographic directions showed that the Fermi surface for conduction electrons in HgSe, although nearly spherical, has slight bulges in the 〈111〉 directions of k space. From the temperature dependence of the amplitudes of the oscillations, it was determined that the cyclotron effective masses of conduction electrons at the Fermi surface ranged from 0. 033 to 0. 068 m₄ for samples having from 1. 8610^17 to 4. 5210^18 electrons/cm^3. This variation of effective mass with electron concentration is consistent with the nonparabolic conduction-band model developed for compounds that have the zincblende crystal structure. The band parameters derived are p=7. 110^-8 eV cm and E₆=0. 24 eV, where P is an interband momentum matrix element and E₆ is the band gap at k=0; these values are in fair agreement with parameters deduced from reflectivity data by other investigators.