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arXiv · 1206.3919

Amplitude modulated drift wave packets in a nonuniform magnetoplasma

P. K. Shukla·A. P. Misra
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Abstract

We consider the amplitude modulation of low-frequency, long wavelength electrostatic drift wave packets in a nonuniform magnetoplasma with the effects of equilibrium density, electron temperature and magnetic field inhomogeneities. The dynamics of the modulated drift wave packet is governed by a nonlinear Schr\"odinger equation. The latter is used to study the modulational instability of a Stoke's wave train to a small longitudinal perturbation. It is shown that the drift wave packet is stable (unstable) against the modulation when the drift wave number lies in $0< k < 1/\sqrt{2}$ $(1/\sqrt{2}<k<1)$. Thus, the modulated drift wave packet can propagate in the form of bright and dark envelope solitons or as a drift wave rogon.

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P. K. Shukla, A. P. Misra. 2012-06-18. Amplitude modulated drift wave packets in a nonuniform magnetoplasma. https://doi.org/10.1016/j.physleta.2012.07.008

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