Negative differential conductivity of electrons in He - Xe mixtures

Abstract

The drift velocity of electrons in He - Xe mixtures is calculated using the two-term expansion of the electron energy distribution function in Legendre polynomials. Collisions of electrons with ground-state and excited atoms are considered, together with Coulomb collisions. The calculations are performed under conditions when negative differential conductivity of electrons occurs. It is shown that concurrent effects of Coulomb collisions and of electron collisions with excited Xe atoms extend the region of parameters in the He - Xe mixtures where negative differential conductivity takes place.