Dynamic properties and the two-point correlation function for electrons in localized coherent Langmuir fields.

Abstract

The dynamic properties for electrons in the localized coherent Langmuir wave fields have been investigated numerically. The Poincar\'e map and the absolute diffusion coefficient account for the existence of regular islands embedded within stochastic regions of phase space. The relative diffusion behavior illustrates that the localized coherent Langmuir wave packets can lead to the formation of a microscale correlation for electrons in phase space. The time evolution of relative quantities further shows that such a microscale correlation has the characteristic of phase-space particle-density granulations, although the electric fields are regular. Finally, the two-point correlation function has been measured by use of the particle simulation technique. That the strong peak behavior of the correlation function can occur only for sufficiently small ${\mathit{r}}^{0}$ and ${\mathit{u}}^{0}$ has been displayed by the simulated results. All these phenomena indicate that the microscale correlation effects (defined also as ``clumps'') indeed exist in our dynamic system.