Drift Velocity and Anisotropy of Hot Electrons innGermanium

The drift velocity and the angle between the direction of the drift velocity and the electric field are calculated as a function of the electric field strength, the crystal orientation, and the lattice temperature. The fit between experimental and theoretical results is nearly quantitative. By the process of fitting, the optical deformation potential constant $D_0$ and the intervalley rate constant $w_2$ are determined. The values $D_0=0.5\mathrm{}\times {10}^9$ ev/cm and $1.66\times {10}^{10} invsec\leqq w_2\leqq {10}^{11} invsec$ are consistent with the results of independent experiments.