Ultrafast dynamics of neutral, ultracold plasmas

The ultrafast dynamics of a neutral, ultracold plasma following an energy landscape shift is studied theoretically and with simulation. To lowest order in time, the inertial dynamics on the new landscape can be characterized by the initial-state plasma microfield, which, for the randomly ordered case of an ultracold neutral plasma, is dominated by nearest-neighbor interactions. Formation of the pair correlation function arises after ballistic overshoot, which leads to oscillations in the effective temperature. Connections are made to similar properties of clusters, photoisomerization of molecules, and nonthermal melting in solids. (C) 2007 American Institute of Physics.