Band structure of cadmium arsenide at room temperature

Abstract

Electron effective-mass values obtained from room-temperature magneto-Seebeck and Hall measurements on ${\mathrm{Cd}}_{3}$${\mathrm{As}}_{2}$ have been gathered from the literature. Using Kane's model for an $\ensuremath{\alpha}\ensuremath{-}\mathrm{Sn}$-type inverted electronic energy band structure, the dispersion related for the conduction band has been obtained along with a ${\ensuremath{\Gamma}}_{8}\ensuremath{-}{\ensuremath{\Gamma}}_{6}$ energy gap of 0.19 eV. Combining these results with the available room-temperature optical data, the relative positions of other bands have been obtained. The heavy-hole valence band, whose maximum is displaced from $\ensuremath{\Gamma}$ by \ensuremath{\sim} 10% of the distance to the Brillouin-zone edge, has a possible small overlap with the conduction band. These two ${\ensuremath{\Gamma}}_{8}$ bands are split at $\ensuremath{\Gamma}$ by a residual gap of \ensuremath{\sim} 0.04 eV. There is a second conduction band whose minimum at $\ensuremath{\Gamma}$ is \ensuremath{\sim} 0.6 eV above the ${\ensuremath{\Gamma}}_{8}$ valence band and perhaps a third one \ensuremath{\sim} 0.4 eV above the latter.