The influence of density in ultracold neutral plasma.

We simulate the evolution of ultracold neutral plasmas using molecular dynamics calculations with open boundary conditions. The calculations use 6000 ions and 6000 electrons, respectively, with a quasi-real ion-electron mass ratio of mi=me = 1000. The simulated plasmas have both Gaussian and ordered initial distributions. While disorder-induced heating is absent in the initially ordered distributions, the ions are heated significantly by electron-ion collisions. We show that the value of the strong coupling parameter typically falls below 10 for realistic plasma densities. [ABSTRACT FROM AUTHOR]