Nonlinear conductivity and composition of partially ionized plasmas in a strong electric field

A partially ionized hydrogen plasma is considered, under the influence of a strong electric field. The nonlinear electrical conductivity is calculated in a self-consistent manner from the quantum transport cross sections of the electron-scattering processes and from a field-dependent nonequilibrium mass-action law in order to determine the plasma composition. Field effects dominate the electric transport properties at low densities because of the high ionization rates. At high densities, a strong increase of the conductivity describes the Mott effect caused by the many-body effects in the dense plasma. A minimum of the degree of ionization and the conductivity assign the interplay between field and many-particle effects. This minimum is reinforced by the field dependence of the mass-action law.