Ultraintense Laser-Cluster Interactions: Effects Of The Cluster Shape

The disintegration of nonicosahedral rare-gas clusters in ultraintense extreme ultraviolet pulses is studied. The clusters quickly form a nanoplasma and evolve only according to the nanoplasma's dynamics, which are determined predominately by the cluster's initial shape. It is found that the cluster's disintegration follows a simple model that is well predicted using only the initial structure. The main finding is that the ions disintegrate tangentially from the surface of the cluster's overall shape. In ellipsoidal clusters, the work done on the ions near the semiminor axis by the other particles (ions and electrons) is larger than the work done on the ions near the semimajor axis. This leads to an inversion of the ellipsoidal axes due to the different axes expanding at different rates.