Experimental Observation of Vertically Polarized Transverse Dust-Lattice Wave Propagating in a One-Dimensional Strongly Coupled Dust Chain

Abstract

Externally driven, vertically polarized transverse dust-lattice waves were observed in a one-dimensional strongly coupled dust chain levitated in the plasma-sheath boundary of a dc argon plasma at low gas pressure around 5 mtorr. Real and imaginary parts of the complex wave number were measured in the experiments. The experimental result clearly shows that the observed transverse dust-lattice wave propagates as a backward wave, which is in good agreement with the theoretical prediction.

Dusty plasma (Yukawa) rings

“…Previous experimental work on 1D dusty plasmas has focused on straight chains confined in highly anisotropic two-dimensional (2D) biharmonic wells [7][8][9][10][11][12]. Such systems have several drawbacks.…”

Rotational modes of oscillation of rodlike dust grains in a plasma

“…Dispersion characteristics of these modes are similar to those of spherical particles of comparable mass and charge, see [10], namely, the optic-mode like "bending" mode related to vertical motions of the centers of mass, and the acoustic mode related to horizontal (in the direction of the mode propagation) motions of the centers of mass. The characteristic frequency of the first mode is determined by the confining potential in the vertical direction; in experiments, and this frequency can be of the order of or higher than the dust plasma frequency depending on the particular experimental conditions [13]. The characteristic frequency range of the acoustic dust-lattice mode is lower, ranging from zero to ω 0 .…”

Large-amplitude acoustic solitary waves in a Yukawa chain

“…For both biharmonic (Homann et al 1997;Misawa et al 2001;Liu et al 2003Liu et al , 2004Liu & Goree 2005) and annular wells (Sheridan & Gallagher 2016), small-amplitude longitudinal waves are found to be well described by the dispersion relation for a Yukawa chain (Melandsø 1996;Homann et al 1997;Liu & Goree 2005;Tkachenko et al 2011;Sheridan & Gallagher 2016), i.e. dust lattice waves.…”