Cross-field electron transport due to coupling of drift-driven microinstabilities in the presence of singly, doubly, and triply charged ion streams

Cross-field electron transport across magnetic field lines plays an important role in fusion, astrophysical, and $\mathbf{E}\times \mathbf{B}$ discharge plasmas. Microturbulence developed due to nonlinear coupling between different linear instabilities has been proposed to be one of the mechanisms responsible for anomalous turbulent transport across the magnetic field. Nonlinear interaction between kinetic instabilities driven by electron drift in crossed electric and magnetic fields ($\mathbf{E}\times \mathbf{B}$ drift) in the presence of multiply-charged ion streams is investigated using kinetic simulations. Singly, doubly, and triply charged ions, streaming in the direction parallel to the applied electric field, interact with electrons drifting in the cross field direction. Microturbulence that develops due to the mode coupling between ion-ion two-stream instability and electron cyclotron drift instability is shown to suppress cross-field electron transport when triply charged ion stream is present. Furthermore, ion trapping in the nonlinear saturation stage of the instability is investigated.