Electron Drift in Gaseous He: Density, Temperature, and Field Dependences

Abstract

The theory of Eggarter and Cohen for the mobility edge of electrons in dense helium gas is used to perform calculations. The experimental low-field mobility is reproduced over its five-order-of-magnitude range as a function of gas density. The recently measured temperature dependence (4-20°K) is also obtained. The low-field Hall mobility is calculated. Finally, modifications are introduced to yield the electric field dependence of the drift velocity, which is also found to be in good agreement with the experimental measurements.