The autoresonant (nonlinear phase locking) manipulation of the diocotron mode in a non-neutral plasma is investigated. Autoresonance is a very general phenomenon in driven nonlinear oscillator and wave systems. By sweeping or chirping the drive frequency, autoresonance allows the amplitude of a nonlinear wave to be controlled without the use of feedback. The experimental results, including a novel scaling relation, are in excellent agreement with a simple theoretical model. These are the first controlled laboratory studies of autoresonance in a collective plasma system.
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Such potentials can cause the diocotron frequency to go up or down, change the sign of nonlinear frequency dependence, and have other curious effects. A study of these effects, in the context of bifurcations in elliptical plasmas, will be published.
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© 1999 American Institute of Physics.
1999
American Institute of Physics
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