Theoretical analysis and dust charge diagnostics in binary complex plasmas

The paper addresses the dynamics of solitary waves in binary complex plasmas, focusing on charge diagnostics for dust particles and its relevance for plasma research, space physics, and fusion applications. The paper uses the reductive perturbation method to derive the Korteweg-de Vries equation for dust acoustic solitary waves in binary complex plasmas. The model successfully explains the phenomena observed in the experiment. Dependence of the amplitude, the width, and the speed of a solitary wave on the plasma parameters are given. Furthermore, a significant breakthrough is the development of a novel charge diagnostic method based on dust acoustic wave speed in binary complex plasmas. This method can be directly tested in a modified gaseous electronics conference plasma chamber and in the Plasmakristall-4 laboratory on the International Space Station under microgravity, providing feasible pathways for experimental validation and future applications. An extended analysis including non-Maxwellian distributions, arbitrary-amplitude solitary structures, spatial inhomogeneity, and dust charging variation further confirms the validity of the dusty plasma fluid model and its relevance to realistic plasma environments.