Fingerprints of different interaction mechanisms on the collective modes in complex (dusty) plasmas

TL;DR

This paper investigates how different interparticle interaction mechanisms influence the collective modes in complex plasmas, showing that long-wavelength dispersion relations can help identify underlying interaction types experimentally.

Contribution

It provides a theoretical analysis linking interaction potential shapes to dispersion relations in dusty plasmas, aiding experimental discrimination of interaction mechanisms.

Findings

Long-wavelength dispersion relations are sensitive to the interaction potential's asymptote.

Different repulsive potentials produce distinguishable dispersion signatures.

The study offers a method to experimentally identify interaction mechanisms in complex plasmas.

Abstract

In this paper we discuss the relations between the exact shape of interparticle interactions in complex (dusty) plasmas and the dispersion relation of the longitudinal collective mode. Several representative repulsive potentials, predicted previously theoretically, are chosen and the corresponding dispersion relations are calculated using the quasi-crystalline approximation. Both weakly coupled and strongly coupled regimes are considered. It is shown that the long-wavelength portions of the dispersion relations are sensitive to the long-range asymptote of the interaction potential. This can be used to discriminate between different interaction mechanisms operational in complex plasmas experimentally. Main requirements are briefly discussed.