Drift wave stabilized by an additional streaming ion or plasma population

It is shown that the universally unstable kinetic drift wave in an electron-ion plasma can very effectively be suppressed by adding an extra flowing ion (or plasma) population. The effect of the flow of the added ions is essential, their response is of the type (vph-vf0) exp[-(vph-vf0)^2], where vf0 is the flow speed and vph phase speed parallel to the magnetic field vector. The damping is strong and it is mainly due to this ion exponential term, and this remains so for vf0 < vph.