Effect of nonparabolicity on Ohmic magnetoresistance in semiconductors

The effect of nonparabolicity of the conduction band of $n-\mathrm{InSb}$ type semiconductors is studied in the framework of the Arora-Peterson density-matrix formalism. To exhibit clearly the effect of nonparabolicity, only the case of elastic electron-acoustic-phonon scattering is considered. Numerical results are presented both for parabolic and nonparabolic models. The nonparabolicity enhances the magnetoresistance, the effect being larger for larger magnetic fields. The Hall coefficient decreases slightly with the increasing magnetic field.