Self-organized zonal flow in the flute-mode turbulence of a plasma

Flute-mode turbulence has a forward spectral cascade unlike the case of drift-wave turbulence. Therefore the linear flute instability may be reduced by this energy cascading toward large wave numbers. As a consequence of three-wave cascade processes derivable from model equations including the effects of density gradient and finite ion Larmor radius the formation of zonal flows in flute mode turbulence is predicted.