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arXiv · 1810.04435

Collective modes of two-dimensional classical Coulomb fluids

S. A. Khrapak·N. P. Kryuchkov·L. A. Mistryukova·A. G. Khrapak·S. O. Yurchenko
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Abstract

Molecular dynamics simulations have been performed to investigate in detail collective modes spectra of two-dimensional Coulomb fluids in a wide range of coupling. The obtained dispersion relations are compared with theoretical approaches based on quasi-crystalline approximation (QCA), also known as the quasi-localized charge approximation (QLCA) in the plasma-related context. An overall satisfactory agreement between theory and simulations is documented for the longitudinal mode at moderate coupling and in the long-wavelength domain at strong coupling. For the transverse mode, satisfactory agreement in the long-wavelength domain is only reached at very strong coupling, when the cutoff wave-number below which shear waves cannot propagate becomes small. The dependence of the cutoff wave-number for shear waves on the coupling parameter is obtained.

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S. A. Khrapak, N. P. Kryuchkov, L. A. Mistryukova, A. G. Khrapak, S. O. Yurchenko. 2018-10-10. Collective modes of two-dimensional classical Coulomb fluids. https://doi.org/10.1063/1.5050708

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