Multitrajectory Dynamics of Cylindrical Particles in the Plasma Sheath Under Low Magnetic Fields

The dynamics of cylindrical nylon dust particles levitated in radio frequency (RF) argon plasma were studied using a plane-parallel discharge geometry. The influence of an external magnetic field of 14–19.5 mT applied using a coil on the lower RF electrode was assessed based on experimental laboratory observations. The crystal structure and dynamics of the particles were examined in the presence of a magnetic field and after switching it off. In the absence of the field, the particles maintained a stable configuration. When the magnetic field was applied, the particles exhibited complex dynamics driven by ion flow resulting from electric and magnetic field interactions. Two distinct behaviors emerged: strongly coupled particles moved collectively in a crystal-like, rotating structure under radial ion forces. Meanwhile, particles at the structure’s edge escaped, following individual, cycloidal trajectories around the long axis. The nonspherical shape of the particles induced a nonuniform charge distribution, which significantly influenced their dynamics. Analysis revealed that the escaping particles experienced a weaker dust–dust Coulomb force compared to the dominant ion drag force. These findings demonstrate the pivotal role of particle shape and competing forces in regulating collective and individual dynamics within magnetized dusty plasmas.