Analysis of Polar Optical Scattering of Electrons in GaAs

Abstract

The theory of the scattering of electrons by longitudinal optical phonons in III‐V compounds is reconsidered, in the nondegenerate limit, assuming a spherical conduction band. The off‐equilibrium part of the distribution function and the Hall‐mobility‐temperature function are obtained with a numerical resolution of the Boltzmann equation, up to a precision of a few 10⁻⁴. The results are compared with previous work due to Sondheimer and Howarth, and Ehrenreich. Application of the theoretical results to high‐purity epitaxially grown GaAs layers is in good agreement around 300°K, but there is a strong discrepancy at higher temperatures. It is suggested that such a discrepancy could be explained by further refinements of the present theory (temperature dependence of the dielectric constant, two‐phonon process).