Lower-hybrid waves have been shown to induce a cocurrent change in toroidal rotation of up to 40  km/s in the L-mode plasma core region and 20  km/s in the edge of the EAST tokamak. This modification of toroidal rotation develops on different time scales. For the edge, the time scale is no more than 100 ms, but for the core the time scale is around 1 s. A simple model based on turbulent equipartition and thermoelectric pinch predicts the experimental results.

A new turbulence-flow cycle state has been discovered after the formation of a transport barrier in the H-mode plasma edge during a quiescent phase on the EAST superconducting tokamak. Zonal-flow modulation of high-frequency-broadband (0.05-1 MHz) turbulence was observed in the steep-gradient region leading to intermittent transport events across the edge transport barrier. Good confinement (H 98y,2 $ 1) has been achieved in this state, even with input heating power near the L-H transition threshold. A novel model based on predator-prey interaction between turbulence and zonal flows reproduced this state well. V

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