Dynamical study and control of drift waves in a magnetized laboratory plasma

The Various dynamical regimes of collisional drift waves in a magnetized pl asma column are experimentally studied. These unstable low-frequency electr ostatic waves are related with strong modulations of the ion and electron d ensity. The angular velocity of the rotating plasma column is the control p arameter of the dynamics: regular, chaotic and turbulent regimes are obtain ed. The spatial extension of the system allows for the occurrence of spatio temporal chaos. The time-delay auto-synchronization method of controlling c haos [K. Pyragas, Phys. Lett. A 170, 421 (1992)] though purely temporal is successfully applied. A numerical study using coupled nonlinear oscillators exhibiting chaos is compared to the experimental results. The control meth od is tested on this model.