Anisotropic diffusion of 2D superparamagnetic dusty plasma liquids.

The diffusion of two-dimensional (2D) superparamagnetic dust grains interacting via both Yukawa and dipole interactions is investigated based on the Langevin dynamics simulation. The magnetic dipole moment, induced by the external magnetic field, is tilted with respect to the 2D layer. It is demonstrated that there exist anisotropic diffusions in the liquid-like state, and the anisotropic diffusions are determined to be the normal type. The anisotropy degree depends on the system temperature and tilt angle of the magnetic dipole, particularly for the latter. Relevance between anisotropic diffusion and pairwise interaction potential energy are examined. The anisotropic oscillations of the system are presented as well.