Quasiparticle approach to the modulational instability of drift waves coupling to zonal flows

The interaction between broadband drift mode turbulence and zonal flows has been studied through the wave-kinetic approach. Simulations have been conducted in which a particle-in-cell representation is used for the quasiparticles, while a fluid model is employed for the plasma. The interactions have been studied in a plasma edge configuration which has applications in both tokamak physics and magnetopause boundary layer studies. Simulation results show the development of a zonal flow through the modulational instability of the drift wave distribution, as well as the existence of solitary zonal flow structures about an ion gyroradius wide, drifting towards steeper relative density gradients.