Dynamics of strongly correlated and strongly inhomogeneous plasmas

Kinetic and fluid equations are derived for the dynamics of classical inhomogeneous trapped plasmas in the strong coupling regime. The starting point is an extended Singwi-Tosi-Land-Sjölander (STLS) ansatz for the dynamic correlation function, which is allowed to depend on time and both particle coordinates separately. The time evolution of the correlation function is determined from the second equation of the Bogolyubov-Born-Green-Kirkwood-Yvon hierarchy. We study the equations in the linear limit and derive a nonlocal equation for the fluid displacement field. Comparisons to first-principles molecular dynamics simulations reveal an excellent quality of our approach thereby overcoming the limitations of the broadly used STLS scheme.

Figure 1

Breathing frequency of three-dimensional (3D) Yukawa clusters with (a) 100 and (b), (c) 200 particles. Comparison of MD simulations, STLS theory, the present ESTLS [Eq. (13)], and a cold-fluid approach [20].

Figure 2

Breathing frequency of (a) 3D and (b) 2D Yukawa clusters with 200 particles and various screening parameters vs coupling parameter. MD simulations (solid lines, filled symbols) vs ESTLS, Eq. (13) (dashed lines, open symbols). The frequencies are scaled to ${\omega }_{\infty }$—the frequency at the largest $\Gamma$ measured in the simulation.