The achievement of a high density and high temperature plasma for a long confinement time is the main goal of controlled thermonuclear fusion research. By increasing the heating power, first a degradation of energy and particle confinement in fusion plasma is obtained (L-mode). Above a certain threshold value of this power, a regime of improved energy and particle confinement (H-mode) is attained. The H-mode is characterized by sharp gradients of the density and the temperature in the plasma edge region, indicating the formation of a transport barrier [1]. This barrier leads to a reduction of the radial transport and a suppression of fluctuations. A localized radial electric field develops in the edge plasma region at the L-H transition. This transition is considered a remarkable self-organization phenomenon in tokamak plasma [2].
In this work I will emphasize a certain striking similarity between the L-H transition in fusion plasma and the appearance of a complex self-organized structure in low-temperature plasmas. Under certain experimental conditions, a complex space charge configuration (CSCC) can appear in form of an ion-rich plasma region confined by a plasma double layer (DL). This CSCC is characterized by steep gradients of density and temperature at the edge. Upon its appearance, a well-localized radial electric field develops in the edge region due to the double layer, which works as a radial transport engine. The high density inside the structure is maintained by the electric field, which enhances the rate of electron-neutral impact ionization. After the appearance of the CSCC the fluctuation level decreases. Similar phenomena were observed in the magnetized plasma of a Q-machine [3].
The experimental results shed a new light on the self-organized model of the L-H transition in fusion plasma.

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