Collective excitations of rotating dusty plasma under quasi-localized charge approximation of strongly coupled systems

Abstract

Collective excitations of rotating dusty plasma are analyzed under the quasi localized charge approximation (QLCA) framework for strongly coupled systems by explicitly accounting for the dust rotation in the analysis. Considering the firm analogy of magnetoplasmons with "rotoplasmons" established by the recent rotating dusty plasma experiments, the relaxation introduced by the rotation in their strong coupling and 2-dimensional (often introduced by gravitational sedimentation) characteristics is emphasized in their dispersion. Finite rotation version of both strong and weak coupling dispersions is derived and analyzed, showing correspondence between a `faster rotating but weakly coupled' branch and its strongly coupled counterpart, relevant to both magnetized and unmagnetized dust experiments, in gravity or microgravity conditions. The first correspondence between their measurements in rotating plasmas and the QLCA produced dispersions in a rotating frame, with an independent numerical validation, is presented in detail.