On the Possibility of Creating Absolute Negative Conductivity in a Local Stationary Plasma With an Inverse EDF

It is demonstrated that the phenomenon of absolute negative electron mobility (ANG) in the homogeneous stationary plasma has a subtle effect when the solution of the Boltzmann kinetic equation is exclusively reduced to the local plasma-chemical balance of electron production and loss. Even if strong electron attachment allows to realize an inverse electron distribution function (EDF), the sign of the electron mobility depends on whether the contribution of the electronegative impurity is also taken into account or not in the increase of the electron scattering transport frequency. In an example of a typical argon–fluorine mixture, it is shown that when real electron collision cross sections are used, the ANG of electrons is not realized even for an inverse EDF. A similar result is obtained when solving a model problem with strong electron attachment: even EDF inversion near-zero energies does not ensure the creation of an ANG. Since a real laboratory plasma is spatially inhomogeneous, in order to find the EDF, it is necessary to solve the complete kinetic equation, which depends on both energy and space variables. Under these conditions, the divergence of the spatial flow is an additional source (or sink), which can thereby ensure the formation of a stationary absolute negative conductivity (ANC).