The Hall mobility and thermoelectric power of p-type lead telluride

A two-valence-band model and the theory of transport in semiconductors with non-parabolic bands have been used to explain the carrier concentration dependence of the room-temperature thermoelectric power and below-room-temperature Hall mobility of undoped and Na-doped PbTe. It was assumed that the scattering is by lattice acoustical phonons. First-order non-parabolicity of the principal valence band can account for the low thermoelectric power of high carrier density material. The Hall mobility has been explained without having unusual temperature and carrier-concentration-dependent effective masses. Band parameters of the simple model were calculated.