Experimental study of nonlinear solitary waves in two-dimensional dusty plasma
- Department of Physics and Astronomy, Ohio Northern University, Ada, Ohio 45810 (United States)
- Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)
The excitation and propagation of solitary waves is studied experimentally in a two-dimensional strongly coupled dusty (complex) plasma. A single layer with {approx_equal}5000 microspheres (8 {mu}m diam) was suspended in an argon plasma with a neutral gas pressure of 3.0 mTorr. The measured Debye shielding parameter was {kappa}{approx_equal}1.6, where {kappa}=a/{lambda} is the ratio of the lattice constant a to the Debye length {lambda}. Nonlinear, planar longitudinal waves were launched by pushing all the particles in a rectangular region at the center of the crystal in the same direction using an 18 W green laser. Compressive solitary waves with density perturbations {delta}n/n{sub 0} < or approx. 0.8 and widths < or approx. 5a were found to propagate in the forward direction at speeds exceeding the dust acoustic speed. For small amplitude solitary waves, the relations between amplitude, width, and velocity are consistent with those predicted for Korteweg-deVries solitons. Rarefactive perturbations were not observed to evolve into solitary waves. However, oscillatory shocks were seen to move in the backward direction after the laser force was removed.
- OSTI ID:
- 21269006
- Journal Information:
- Physics of Plasmas, Vol. 15, Issue 7; Other Information: DOI: 10.1063/1.2955476; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of positron density and temperature on ion-acoustic solitary waves in a magnetized electron-positron-ion plasma: Oblique propagation
Dust-acoustic solitary waves in a four-component adiabatic magnetized dusty plasma