Superdiffusion of two-dimensional Yukawa liquids due to a perpendicular magnetic field

Abstract

Stochastic transport of a two-dimensional (2D) dusty plasma liquid with a perpendicular magnetic field is studied. Superdiffusion is found to occur especially at higher magnetic fields with β of order unity. Here, β=ωc/ωpd is the ratio of the cyclotron and plasma frequencies for dust particles. The mean-square displacement MSD=4Dαtα is found to have an exponent α>1, indicating superdiffusion, with α increasing monotonically to 1.1 as β increases to unity. The 2D Langevin molecular dynamics simulation used here also reveals that another indicator of random particle motion, the velocity autocorrelation function, has a dominant peak frequency ωpeak that empirically obeys ωpeak2= ωc2+ωpd2/4. © 2014 American Physical Society.