Effect of dust–dust interaction type on normal modes of two-dimensional dust crystals

Abstract

Dispersion relations for longitudinal and transverse dust lattice waves in two-dimensional hexagonal dust crystals of negatively charged particles were investigated and compared for two different interaction types, namely, Coulomb and screened Yukawa potentials. Results showed that the interaction type and the wave propagation direction change the characteristics of the dispersion relation as well as the group velocity. The screening parameter is also found to reduce the mode frequencies.