Galvanomagnetic Phenomena in High Electric Fields

The Hall coefficient in a many-valley semiconductor is calculated for high electric fields and is shown to be independent of the electric field. For silicon we find $\frac{R_{100}}{R_{111}}=0.9\mathrm{}$ and $\frac{R_{110}}{R_{111}}=0.85\mathrm{}$, where $R_{100}$ is the Hall coefficient for the current in the [100] direction, etc. For germanium we find $\frac{R_{111}}{R_{100}}=0.68\mathrm{}$. Distribution functions for hot electrons in high magnetic fields are calculated at high and low temperatures for acoustical phonon scattering.