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Nonlinear dynamics of the magnetic electron drift mode turbulence is outlined and generation of large-scale magnetic structures in a nonuniform unmagnetized plasma by turbulent Reynolds stress is demonstrated. A two-component turbulent system consisting of magnetic fluctuations and generated secondary flows is considered. The evolution equations for mean magnetic flow generation are obtained by averaging the two-field model equations over fast small scales. It is found, in turn, that the pattern of the flow modulates and regulates the turbulence dynamics. The main features of the flows are controlled by the structure of the nonlinear coupling to the small-scale magnetic fluctuations as well as by the spectral properties of the turbulence and its anisotropy. Thus, the parent waves and secondary magnetic flows form a self-regulating system. It is shown that the presence of large-scale structures leads to shearing of turbulence. The k-space diffusion coefficient for the magnetic zonal flows and streamers are...

Generation of large-scale flows (zonal flows and streamers) by flute mode turbulence is examined. The evolution equations for mean flow generation are obtained by averaging the model equations over fast small scales. For a system containing both drift-type waves and large-scale structures, small scales are modulated by larger scale shear flows so that energy in the small-scale component is not conserved. A WKB-type wave kinetic equation that describes the conservation (along the rays) of an action-like invariant of the flute mode turbulence with slowly varying parameters due to the mean sheared flow is formulated. The relevant action-like integral is shown to correspond to the quantity conserved for the small-scale component alone. The structure of the action integral is determined by the structure of the matrix element describing the interaction of the small-scale and large-scale component. The k-space diffusion coefficient for the zonal flows and streamers are calculated.

The properties of streamers and zonal magnetic structures in magnetic electron drift mode turbulence are investigated. The stability of such large scale structures is investigated in the kinetic and the hydrodynamic regime, for which an instability criterion similar to the Lighthill criterion for modulational instability is found. Furthermore, these large scale flows can undergo further nonlinear evolution after initial linear growth, which can lead to the formation of long-lived coherent structures consisting of self-bound wave packets between the surfaces of two different flow velocities with an expected modification of the anomalous electron transport properties.

The properties of zonal and streamer flows in the flute mode turbulence are investigated. The stability criteria and the frequency of these flows are determined in terms of the spectra of turbulent fluctuations. Furthermore, it is shown that zonal flows can undergo a further nonlinear evolution leading to the formation of long-lived coherent structures which consist of self-bound wave packets supporting stationary shear layers, and thus can be characterized as regions with a reduced level of anomalous transport.